ISSN:0306-1353    

DOI:10.1039/AA97808FX001

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

a -- - -- == Thechemical Society - -/ Analytical Sciences Monographs\A series of monographs on topics of interest to analytical chemists.High Precision Titrimetryby C. Woodwardand H. N. RedmanThis monograph describes how, using simple, inexpensive equipment, titrimetric procedurescan obtain results of superior precision to those achieved routinely in the laboratory. The bookdeals with visual titrations, including apparatus and preparation of substances; and in-strumented titrations, including photometric and electrometric techniques.Paperbound8i" x 6' 71pp €2.50/$5.mThe Chemical Analysis of Water- General Principles and Techniquesby A. L. WilsonChemical analysis of water for human consumption has been the subject of countless books,and this volume concentrates on a critical appraisal on the analytical principles involved. Allstages of the analytical process are covered, including: sampling of time, place and techniques:the analysis proper; the reporting of results, and data handling.Clothbound 196pp 8%'' x 4." €7.50/$15.mPyrolysis- Gas Chromatographyby R .W. May, E. F. Pearson and D. ScothernThis volume presents the available knowledge on the subject of pyrolysis-gas chromatography ina form useful to the analyst. Areas covered include: merits and demerits of particular ap-plications; major analytical uses of the technique; identification of the pyrolysis products whichare eluted from the chromatography column, and the necessity for increased standardization.Clothbound 117pp 8%" x 6' f 7.20/$14.10Electrothermal Atomization for Atomic Absorption Spectrometryby C.W. FullerOne of the successful alternative atomization sources to the flame is at present electrothermalatomization, and this volume deals with all aspects of this technique, including: history;theoretical aspects: practical considerations; analytical parameters of the elements; and specificareas of application.Clothbound 135pp &" x S" €6.75/$13.50Dithizoneby H. M. N. H. IrvingAs a result of his long association with analytical techniques using this reagent, the author isable to present in this volume a body of historical and technical data on the subject. Specifictopics include: the properties of dithizone; metal-dithizone complexes and their formulae: thephotochemistry of dithizonates; and organometallic dithizones.Clothbound 112pp 8%" x 3" f 7.25/$14.50Further information about any of these publications can be obtained from: The MarketingDepartment, The Chemical Society, Burlington House, London WIV OB

ISSN:0306-1353    

DOI:10.1039/AA97808BX003

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

CHAPTER 2 Instrumentation 2.1 LIGHT SOURCES The increasing range of applications of lasers has necessitated that work relating to specific areas, e.g., laser AFS in flames, be reported in the appropriate Sections (see 1.1.1 and 1.33. Only developments in laser sources, and those studies that are of a novel or fundamental natures will be dealt in this Section. There has been considerable interest in using lasers to promote ionization of atomic species with subsequent detection of the liberated electrons.Techniques based on this principle can measure concentrations of elements below the ppb level. The tern 'single atom' detection i s frequently quoted by some authors; it must be stressed that this is some- what misleading and the measurement is often of individual atoms from a much larger atom population.The detection of individual atoms of Cs using resonmce ionization spectroscopy has been the subject of additional work by Young et al. (52, 558) (ARAAS, 197V, 7, 32) and has also been discussed in a review by Robinson (793. It has been suggested that the two-photon method used to ionize Cs is only applicable to a few other alkali metals because the com- bined two-photon energy from currently available lasers is insufficient to ionize most other elements.However, it has been shown that it is possible to extend the range of application of this technique by using two lasers simultaneously. Atoms absorb one photon from each laser and reach a much higher energy level than with a single laser. Ionization ensues by the absorption of a third photon from either laser.This procedure has been applied to the detection of Na (79). 'Bekov et 02. (1366) used a three-laser excitation system with field ionization to detect individual atoms of Yb. A narrow beam of Yb atoms was excited into Rydberg states by radiation from three tunable pulsed dye lasers and ionization was effected by a field voltage pulse of 12-14 kV cm-1.The authors claimed that their method is preferable to direct laser ionization for heavy elements with complex spectra, and for those with ionization potentials greater than 6 eV. It was also claimed that the laser power required was reduced by several orders of magnitude. @Haverand Harnly (1 38,956) compared the radiant intensity of a 300 W Eimac continuum source with that of conventional HCLs over the spectral range 194 nm (As) to 588 nm (Na).They used an echelle spectrometer with a band-pass of 0.002-0.006 nm and compensated mathematically for the residual difference in resolution between the continuum and line- source emission profiles. Surprisingly, the Eimac lamp was reported to be 2-500 times more intense than conventional HCLs for the 29 lines in the region studied.An echelle spectro- meter, which must be used for AAS measurements with the Eimac source, has a lower overall light throughput than a medium resolution monochromator typically used with HCLs. A comparison of the relative light fluxes through the two types of system showed that the Eimac-echelle Combination resulted in a greater light throughput at wavelengths above 300 nm, but lower throughputs below 300 nm, and, in some cases, significantly worse AAS detection limits. There has been renewed interest in the development of high-intensity or boosted- discharge hollow-cathode lamps for AAS and AFS.Myers (1373 described a demountable high-intensity HCL with interchangeable cylindrical cathodes and with the secondary high- current booster discharge in line with the direction of the light emission.This configuration 3132 Andytical Atomic Spectroscopy was reported to give better AAS sensitivity, at the same lamp emission intensity, than lamps with the booster-discharge at right angles to the direction of light emission, Increased emission intensities were reported for Al, Cu, Mo, Ti and V with almost no loss in sensi- tivity by comparison with EDLs or other high-intensity HCLs.When operated at 10 times the intensity of a conventional HCL, the cylindrical high-intensity lamp produced absorb- ance values of not less than 90% of the equivalent HCL. Sullivan and Gough (682) used boosted-discharge lamps for non-dispersive flame AFS and obtained detection limits (water matrix) of < 0.2 ng ml-1 for Ag, Cd, Cu and Zn and 1.5 ng ml-1 for Ni. Novak and Browner (W7, 9157) have evaluated pulsed and continuously operated microwave EDLs, r.f.EDLs and HCLs. They found that under their operating conditions pulsed r.f. Ems showed less self-reversal than pulsed HCLs, and that pulsed lamps gave improved analytical sensitivities for AAS and AFS measurements of Cd, Hg and Zn (957).The resonance intensity ratios of r.f. to microwavc EDL3 were: Hg greater than 1, Cd equal to ca. 1, Zn less than 1. The authors suggest that the maximum intensities have not yet been reached and that pulsed r.f. EDLs will become important sources for AFS. White- side and Price (1343) reported the development of r.f. EDLs for T and P. Thcy measured I in aqueous solutions in the range SO-100 pgml-1 and P in steels from 10~30 pg g-1 using ETA-AAS. Other references of interest - Studies of quenching of fluorescence: 147. Effective cross-section in photoionization: 1337.Ionization studies on Ba: 1338. Laser microprobe analysis: 174. Comparison of HCL and flow discharge source: 795. Determination of C in cast-iron glow discharge: 4'3 Electron temperatures in HCL discharge : 779.Multi-element analysis of steels in boosted glow discharge: 687. Simplex optimization of pulsed operation of HCL: 349, 778. 2.2 omcs 2.2.1 Background Correction Bath et al. (958) described a background-correction system for AAS in which a double- windowed HCL was placed between the H lamp and the graphite furnace. The continuum radiation passed directly through the open-ended cathode of the analyte HCL.This ensured precise optical alignment of the two beams. The inconvenience and expense of double- windowed HCLs was offset by using a continuously pumped demountable HCL. Zeeman-effect background-correction systems are becoming increasingly used in AAS and their application has been reviewed (400). Murphy and Stephens (1146) reported the use of the Zeeman effect in AAS with commercially available HCLs powered by r.f. sources and maintained in a magnetic field.They showed that for Cu, Fe and Zn HCLs the intensity and stability characteristics of normal d.c. operation could be maintained under Zeeman- effect conditions. 2.2.2 Optical Systems Lipari and Plankey (946) described a coir tinuurn source instrument for AFS.Wavelength modulation was incorporated by using an oscillating interference filter, which acted both as a spectral isolator and a background corrector device. Detection limits using Ar sheathed air/C,H, flames were 0.02 pg ml-1 and 0.0025 pg ml-1 respectively, for Cu and Mg in serum. The equipment is to be evaluated for an ETA system.Chapter 2: Znstrumentation 3,3 Wavelength modulation using an oscillating mirror has been used in conjunction with a rapid scanning spectrometer for multi-element determinations by AES (41 8).This system is an improved version of that reported earlier (Analyst, 1976, 101, 753) with a higher resolu- tion grating and improved galvanometer mirror size. The system was tested using ETA-AAS and AES with both carbon cup ETA-MTP, and nebulization /desolvation-MIP.Spectral isolation employing a sputtering low-pressure discharge as a resonance mono- chromator has been used for the analysis of metals in steels using a glow discharge source (5231. Other references of interest - Modular Michelson interferometer for Fourier transform spectroscopy, U.V. to mid-i.r.: 766. Off-axis imaging for improved resolution and high spectral intensities: 1012.Stigmatic spectrograph image intensifier system: 1087. 2.3 DETECTORS AND DATA PROCESSING 2.3.1 Introductidn The use of rapid-scaiirting photoekctric detectors (imaging-type detectors), such as vidicon television camera tubes and solid-state photodiode arrays, for AAS and AES, was first reported in 1973 (ARAAS, 19133, 3, Ref. 12859. In the years following, many applications of multi-element determinations were described. This year, for the first time since 1973, a decline in their reported usage has occurred and much of the published work describes the data processing systems which are so important for the efficient application of imaging-type detectors to multi-element AES and AAS. Almost all the publications reporting other detection systems, including photographic emulsions and conventional photoelectric devices (photomultiplier tubes), describe develop- ments in data processing. 2.3.2 Rapid Scanning Photoelectric Devices The most popular detectors of this type are SSIDs. Chuang, Natusch and O’Keefe (949) have used a 1024-element photodiode array for multi-element FAAS. Up to three analytes were determined simultaneously and the authors’ findings concurred with those of previous workers in that detection limits were poor compared with conventional single-element analysis.A further disadvantage is the limited wavelength range obtainable if resolution is to be maintained. Bubert et al. (1065) used a 5-element array, with individual diode outputs, of the type first evaluated for multi-element FAES by Boumans et al.(Spectrochim. Acta, 1972, 27B, 247). They have developed an improved readout system and have compared SNR performance with photomultiplier tubes (PMTs). A linear dynamic range of more than 5 orders of magnitude, referred to the noise level, was claimed. A photodiode array detector has been coupled to an ICP spectrometer by Holrlick and co-workers ($74, 1269).They have developed an elegant and ingenious way of improving selectivity by using a hardware cross-correlator to store a reference spectrum (7’65). In operation, the reference spectrum is multiplied by the sample spectrum and integrated to indicate the presence of common features in the spectrum. Spectral interferences are thus minimized, and it is suggested that this procedure providcs similar selectivity to the ‘lock-and-key’ detection system of FAAS.Codding and Hwang (404) have also described the application of crms-correlation using a photodiode array for FAES. Unlike Horlick‘s system, however, theirs did not perform real-time correlation, because recall of the reference spectrum from computer memory was required.34 Anolytical Atomic Spectroscopy Little further work with vidicon detectors has been reported, though Pardue and co-workers remain active in this field.Hoffman and Pardue (10083. have adapted an auto- ranging amplifier to a vidicon spectrometer. They report some improvement over the system without autoranging, including an extended linear dynamic range. Image-dissector (ID) tubes have sensitivities similar to those of photomultiplier tubes.During the last few years, their use for multi-element work has provided improved detec- tion limits and enabled higher resolution than either SSIDs or vidicons. Felkel and Pardue (905) have separately coupled a silicon-target vidicon tube and an ID tube t o an echelle grating spectrometer for multi-element determinations with a d.c. plasma source (Spectro- metrics model 53000).They found improved resolution and greater dynamic range with the ID, which also gave limits of detection similar to those obtained with photomultiplier tube detection, The same authors have used the image-dissector echelle spectrometer for multi-element analysis by FAAS (557, 925). Limits of detection were reported to be lower than with the silicon-target vidicon.Other references of interest - SSID interfaced with a microprocessor-based signal sampling electronic circuit: 93'9. SNR studies of photodiode arrays used with ICPs: 149. 2.3.3 Emission Spectroscopy Photographic detection /recording, though now little used for quantitative spectroscopy, still has certain advantages over photoelectric methods.Wide wavelength coverage is available in a single exposure, while high resolving power is retained, The use of photo- graphic detectors with E P s requires a higher standard of microphotometric performance compared with conventional excitation sources in order to exploit their improved precision. Some workers have examined microphotometric measurement methods with a view to improving their performance.Torok and Hafenscher (1044) examined scattered-light inter- ference in a microphotometer, which had led to S-shaped characteristic curves. Procedures for correcting these measurement errors were described. McGonagle and Holcombe (793, 190) predicted microphotometric conversion errors by means of a computer simulation program. They emphasized the importance of microphotometer slit width in reducing errors.Zimmer and Heltai (1047) have modified a Zeiss GI1 microphotometer to obtain improved signal stability and a reduction in the amount of scattered light. Advances in direct-reading OES have involved mostly data processing. Ajhar et al. (1 17) have described a digital readout system with bus type data transfers. Jarrell et al.(87) demonstrated how computer correction folr matrix background effects reduces the need for separate calibration when the concentrations of major components change. A new curve- fitting equation was described by Crawford (84, 14'18) and was claimed tcu produce more exact calibration curves over a concentration range up to 4 orders of magnitude. The use of APL (a programming language) to convert the output of a Jarrell-Ash ICP spectrometer into a reportedly more manageable form has now been published by Capar and Dusold (1 165).Further data manipulations, such as calculation and presentation of results, statis- tical tests and archival storage, were carried out by a remote computer. Automatic back- ground correction in a sequential OES spectrometer has been described by Walters (1439).The background was determined on both sides of the analytical line sequentially at pro- grammable positions. Haas et al. (115) have applied this principle to a direct-reading spectrometer used for ICP-OW. A minicomputer-controlled stepping motor automatically stepped the entrance slit along the focal curve of the polychromator, enabling emission intensities at preselected wavelengths in the region of the analysis line to be measured, An intriguing procedure for correcting drift in a direct-reading emission spectrometer has beenChapter 2: Instrum en tation 35 described by Chapman and Gordon (7'67).A 1000-W tungsten-halogen lamp was used to provide a reference signal for each optical channel, using identical optical components to those used in the measuring procedure.This avoided the need to use analytical reference standards to make drift corrections. Other references of interest - BASIC algorithms for ICP-OES: $82. Computational procedures for characterizing spark sources : 774. FORTRAN program for analysis of spectral data: 1005. Microprocessor-controlled readout system for PMTs: 398. 2.3.4 Absorption Spectroscopy The use of on-line data processing and instrument control by microprocessors is increasing. New commercial instruments incorporating microprocessors are described in Section 2.4.2. Franke (9934 has reviewed their use in analytical instrumentation with reference to FAAS. Routh (139, 1353) has described how, when compared with analogue electronics, they give improved accuracy and precision and extend the analytical working range for many elements. A useful paper by Futrell and Morrow (216) explained the interfacing of any commercial double-beam atomic absorption spectrometer to a programmable calculator. The interface electronics were easily constructed, and the calculator could be removed from the instrument for off-line use.Heinemann and Prinz (1294) have described a computer program for calculating concentrations from absorbance values with a desk calculator.A low-cost data-processing system described by Stockdale, Whiteside and Newstead (135) used magnetic card programs that allowed the choice of calibration and curve- correction method best suited to a particular analysis. They also developed programs for standard addition calibrations, automatic sampling systems and calibration with CRMs.The authors suggested that the greatest benefit of using these programs would be derived in work with ETA. Two particular problems associated with ETA mcthods are the transient nature of the signals and the need for a highly effective background-correction system. Lundberg (781) has described a digital system capable of recording both peak height and peak area.Siemer (776) has cautioned users of instruments which exploit continuum-source background correction that inadequate rejection of d.c. emission from a graphite furnace can occur. Some improved techniques for constructing calibration curves have been presented. Andrews (841) used a numerical method based on the assumptions that the relationship between absorption reading and concentration is described by an exponential equation and that the concentrations of standard solutions form an arithmetic progression. A computer program, CURVE, has been used (212) to calculate theoretical calibration graphs, taking into account the influences of hyperfine structure, variable emission and absorption line half-widths, and atomization processes. Other references of interest - Automatic sample preparation and data handling in AAS: 296.Categorization by trace metal content using ETA-AAS and pattern recognition techniques: 63'4. Errors in computer data handling: 100.2. Microprocessor-based low-pass filter: 976. Resonance monochromator for AAS: 140.36 Analytical A tomic Spectroscopy 2.4 COMPLETE INSTRUMENTS 2.4.1 Emission Instruments Plasma sources (especially ICPs) are now firmly established in OES and are incorporated into many new commercial instruments.A sophisticated new direct-reading spectrometer from Jobin-Yvon, the JY-48 (1 19), makes use of a holographic diffraction grating to obtain a reduction of stray light, increased SNR, higher dispersion and larger spectral coverage than those obtained with ruled gratings.The computer controlled instrument is available with both arc/spark and ICP sources. A lower priced alternative to. a direct-reading spectrometer, also from Jabin-Yvon, is the JY38P (85). This instrument (ARAAS, 197’7, 7 , 54) can determine sequentially up to 38 elements. It uses an ICP source and a high-resolution holographic grating monochromator.Butterworth and Lloyd (920) have evaluated an E P spectrometer, the ARL 34000/ICP, for steel analysis; good long- and short-term precision was obtained, the only difficulty reported being corrosion of the plasma torch when test solutions contained fluoride. The ARL 34000 Quantometer with ‘Unisource’ spark excita- tion was also evaluated for this application by Butterworth and Irons (919); although short- term precision was acceptable, the long-term stability was inferior to that of an ARL QV80 spectrometer.A new polychromator design has extended the useful wavelength range of the Angstrom V-70 optical emission spectrometer (168). Two diffractioa gratings were placed in series, and the second grating was illuminated by the zeroborder radiation from the first grating.Wavelength ranges for the two gratings were 160440 nm and 400-790 nm. Horlick and co-workers (874, 1269, 765) have constructed an ICP spectrometer using a photodiode array detector (see Section 2.3.2.). The use by Yeung et al. of a Fabry-Perot interferometer for multi-element FAES has been previously described (ARAAS, 1976, 6, Ref. 735) and at that time detection limits were poor.A second-generation instrument has no’w been evaluated by Korba and Yeung (1243, 1317). Improved optics yielded detection limits and linearity of response that compare favourably with those in conventional single-element analysis. Results were presented for simultaneous determinations of up to 3 elements in tap-water, standard orchard leaves, steel, urine and blood serum.Spectral interferences in FAES were automatically corrected in a Russian double-beam spectrometer (6033, which used a high-transmission high-resolution double-grating mono- chromator, 2 PMTs and a 2-channel d.c. amplifier. New spectrograph for the v.u.v.: 1050. Study of the characteristics of a copper arc: 13\67. Other references of interest - 2.4.2 Absorption Instruments Most new commercial instruments incorporate microprocessors. Apart from the obvious benefits of convenience and ease of operation, microprocessors are frequently claimed to improve the analytical performance of instruments, giving improved precision, accuracy and dynamic rang2 when compared with instruments with analogue signal processing.The most sophisticated of this new generation of instruments i s probably the Perkin-Elmer model SO00 atomic absorption spectrometer.This i s a double-beam instrument with back- ground correction, which allows fully automated sequential multi-element analyses (1 26, 12$, 1163). A microcomputer stores analytical parameters for up to 6 elements in 6 separate memories. These parameters, once established, can be stored on magnetic card to facilitate re-use of the program.The microcomputer not only receives analytical data and performs instrument calibrations but also controls all mechanical settings. Thus wavelength, gas flow, flame conditions, and lamp are automatically changed for each element to beChapter 2: Instrumentation 37 determined. Finally, the use of an automatic sampler avoids the need for continuous operator attention.Very rapid analysis bas been claimed (128) with 300 determinations (6 elements in 50 samples) being performed in as little as 30 min. A new atomic absorption spectrometer from Instrumentation Laboratories is the model 551. This is a double-beam instrument with a microcomputer performing all those functions now regarded as normal in such equipment: e.g., touchbutton selection of operating para- meters, automatic calibration, etc.An additional feature, however, i s a visual CRT display providing rather more flexibility than instruments with only digital or hard-copy display (1 3'4). Further applications of the use of the Instrumentation Laboratories model 751 (ARAAS, 1977, 7, Refs. 1054, 10633 have now been published (332, 1256). These include the analyses of river waters, drinking waters, cements, steels, ores, fertilizers and gunshot residues. The working range may be increased for this instrument by determining the same element in both channels but at different wavelengths. Several new atomic absorption spectrometers have been reported in the USSR (320, 334, 340, 1022, 10283, and at least two of these incorporate microcomputers.Continuum source AAS generally suffers from problems of poor detection limits, reduced linear working ranges and stray light interferences, unless a high-performance monochromator i s used. Cochran and Hieftje (964) developed a selective spectral-line modulation atomic absorption instrument which partly overcame these problems.Radiation from an Eimac continuum source was directed through the analytical flame cell and then a mirrored chopper directed the radiation alternately through and around a second cell containing a preselected concentration of the analyte. In this way selective modulation was achieved and a medium resolution monochromator could be used. Analytical sensitivities similar to those obtained by conventional line-source AAS were obtained, though detection limits were litttle improved over those of conventional continuum-source AAS.A problem of using AAS for multi-element analysis is the multiplexing of radiation from suitable line sources. Salin and Ingle (125) have succeeded in combining the radia- tion from 4 sequentially pulsed HCLs by means of carefully aligned beam splitters, and directing the combined beams through a single monochromator.A multi-slit mask was mounted in the focal plane of the monochromator and all radiation was focussed onto the same PMT by means of a mirrored funnel. It was claimed that this relatively inexpensive system could be made by adapting an existing single-element instrument. A multi-element FAAS spectrometer using a photodiode array detector has been evaluated by Chuang et aZ.(949). This system is described in Section 2.3.2. An automatic sampler for FAAS has been produced by Perkin-Elmer (701). The model AS50 features a key-board with built-in &bit microcomputer, which can be used to control the sampling system and the parent spectrometer. Instrumentation Laboratories have intro- duced an automatic sampler for their graphite-furnace atomizer (1 3541, based on Matousek's design (ARAAS, 1977, 7, Ref. 489) in which samples were nebulized for 1-100s into the furnace at 150 "C. It is to be expected that besides the obvious autosampler advantages of speed and convenience, precision should be improved, since the difficulty of reproducible pipetting of microsamples has been removed.Other references of interest - Computer-controlled photon-counting spectrometer: 790. Zeeman atomic absorption spectrometer with an improved spectral lamp: 449. 2.4.3 Fluorescence Instruments A difficulty of FAFS, which may be largely responsible for the absence of any current commercial instruments, i s that of obtaining sufficiently stable high-intensity light sources.However, Michel et al. (5, 144, 716) have developed a sophisticated instrument using a38 Analytical Atomic Spectroscopy high pressure xenon arc or EDLs, and it was claimed that the lack-of-stability problem of the EDLs had been overcome by their reproducible preparation using a simplex algorithm. Another common problem of FAFS, the introduction of stray light into the monochromator, was minimized by using a double monochromator system.This, together with a background correction procedure, led to a high SNR. Although detection limits have not bcen quoted, the determination of Cd in urine at conccntrations of <0.5ppb has been described, The production of instruments such as this could lead to a new surge of popularity for FAFS.Wavelength modulation for an Eimac continuum source atomic fluorescence spectro- meter has been achieved by use of an oscillating interference filter between the source and the flame (149,946). Detection limits for Cu and Mg were an order of magnitude poorer than those obtained by other flame spectrometric techniques; the major noise was probably from flame flicker due to the wide band-pass filter used.The authors suggested that the system might be more effective if used with a low background atomizer such as an ETA. In an instrument described by Ullman er al. (1531, wavelength modulation was achieved by the use of a quartz refractor plate /torque-motor assembly in the monochromator. Other flame AFS instruments have been described by Dittrich et al.(69), who used an EDL source with ETA, and by Gough and Meldrum (685), who used a cathodic sputtering source. 2.44 Magnetically Induced Optical Rotation This technique has been examined by Stephens (1 380) for the spectrometric determination of Hg. Radiation from an EDL was passed through a silica-tube atom reservoir positioned between crossed polarizers within a longitudinal oscillating magnetic field.Whcn the a.c. components of the transmitted radiation were measured, the photmultiplier tube signal was proportional to the angle of rotation of the plane of polarization, and to the analyte concentration. Picogram detection limits were claimed and the selectivity was said to be as good as that of AAS. Moreover, the system was insensitive to continuum background absorption and source drift. 2.5 NEW COMMERCIAL INSTRUMENTS 2.5.1 Emission and Plasma Spectrometers The use of ICP sources for emission spectroscopy continues. Spex Industrics have introduced the 1269, a scanning spectrophotometer for research purposes, for which a claim of very high resolution i s made. It has a focal length of 1.26m and a reciprocal dispersion of 0.65 nm mm-1.Spectroscandia AB have closed down and presumably the IDES 2080 has been withdrawn. 2.5.2 Atomic Absorption Spectrometers The increasing use of microprocessors continues and video screen displays are being intro- duced. Perkin-Elmer have replaced or renumbered their range of AAS instruments; the 280 replaces the 272 and the 380 the 37'2, both these models being microprocessor con- trolled.The 560 replaces the 460, with the addition of statistics, and the 703 replaces the 603. Instrumentation Laboratorics have introduced three new instruments, all of which are microcomputer controlled. Each has optional background correction, alpha- numeric printers and wavelength scan facilities. The 551 has a five-standard calibration and a memory that will store up to 10 calibration curves simultaneously.A video screen displays standard conditions for each element together with a working curve, and will also showChapter 2: Instrumentaiion 39 transient absorbance signals. The 157 and 257 have a two-standard calibration, which can be up-graded to five standards if required. Pye Unicam have withdrawn the SP1950 and and SP1900 and have introduced the SP9, a single-beam instrument with deuterium back- ground correction, The ‘computer’ version of the SP9 has curve correction with up to five standards in fixed or variable ratios, peak height or peak area read-out and full statistics. Varian have introduced a new single-beam instrument, the AA275, and two double-beam instruments, the AA475 and AA775.The AA275 and AA475 are both microprocessor controlled with a three-standard calibration, and the AA775 is fully microprocessor cm- trolled with a five-standard calibration, statistics, and standard additions calibration, The AA7’75 has a minimum resolution of 0.05 nm.There are two new electrothermal atomizers; Perkin-Elmer have replaced the HGA2200 with the HGA400, which has direct programming, by keyboard entry, of temperature, range time, hold time, gas, and other spectrophotometer controls, and digital display of temperature, time and programme status.Pye Unicam have two versions of the SP9 graphite-tube furnace. The SP9 video furnace has video display of status and storage for 9 furnace programmes. The SP9 fits all Pye Unicam AAS instruments and has digital display of remaining time; both instruments have built-in autosampler controls.S. & J. Juniper have ceased production of the 110 graphite furnace.Table 2.5A COMMERCIALLY AVAILAB'LE EMISSION SPECTROMETERS 8 Reciprocal Supplier Model Type c/&& cllp~er;lon~ ~~~~~~h EGA Type of source Speclal features Appllcatlons Applied Research Laboratories Ltd., Wingate Road, Luton, Beds., England Quanto- DR 48 0.465 170-407 1.0 m Low voltage, meter 0.520 193-456 1.0 m high voltage or 34000C 0.347 or 0.694 190-610 1.0 m d.c.arc 0.930 or 0.465 190-820 1.0 m of 0-310 Applied Research Laboratories Ltd., En Vallaire, Ecublens/ La u s a n n 8, Switzerland Applied Research Laboratories Ltd., 9545 Wentworth Streel, P.O. Box 129, Calif., U.S.A. CH-1024 SociW Francais d ' l nstruments de Controiee d 'Analyses, B.P.No. 3, Le Mesnil St., Denis, France F-78320, Quanto- DR 60 As 34000C As34000C As Low voltage B34OOOC high voltage meter 34000C and/or and/or d.c. arc Quanto- DR 48 meter 34000D Quanto- DR 60 meter B34000D Quanto- DR 34000/ Ag Cap meter test Quanto- DR Q uant o- scan Scan./ DR 48 10 Unlimited As 31000C As 34OOOC 0.465 0.70 0.80 0.60 0.50 0.40 A t 3400UC As 34 ODOC As 34OOOC As 34 oooc 170-407 1.0 m 2000-4000 0.3 m 190-880 1.0m 190-670 1.0 m 175-550 1.0 m 175460 1.0 m Fully computer controlled to provide direct concentration print-out; full range of options including dual cassette, dual floppy discs, visual- display units, fast printers, remote terminals and computer links etc; air or Ar excitation stands twin stand facility Including Ar, air, hollow cathode, rotrode, plasma, etc.AS 34000C. As 34000C Fully calculator controlled t o provide direct concentration print-out: optional local and remote printers; Ar or air excitation stands twin stand facility Including Ar. air, hollow cathode, rotrode, plasma, etc. As B34000.C As 34000D; Low voltage As 34OUCC; remote aerosol generator excitation head Low voltage Small transportable Quan t om et er with GO-NO GO inspection type electronics Low voltage, Automated scanning high voltage grating for wavelength d.c.arc range studies; profile facilities and electronics providing quantitative analysis on chosen spectrum lines As 34000D but particularly suited to the analysis of highly alloyed maierials; computer options available to allow incorporation into plant systems As B34000D; offers comprehensive computer options to handle multiple and complex alloy programmes All ferrous and non- ferrous materials and powders, including slags, rocks, soils, etc.As 3400OD; allows for expanslon to include a large number of elements and the use of twin stand combinations such as Ar/air where necessary AIIOWS analysis of large R, castings, forgings etc '1, remote from insirument 6- EL Size and operation allowsrapid on the spot $ 3 analysis of incoming and S' out going materials b 'h Low cost instrument 2 offers an unlimited choice of elements; suitable for semi- : research and general applications where sample throughput is low 5Wuanto- Scan./ Unlimited As As As As Quantoscan As Quantoscan but scan DR Quantoscan Quantoscan Quanto- computer controlled computer scan wavelength selection controlled ' Various available i n 'Varisource' unit, including spark, low- and .high-voltage d.c. arcs. blso versatile controlled wave-excitation source'. ICP As Quantoscan ' Wadsworth spectrograph; 20 inch camera 20 inch camera Choice of 3 gratings; NZ purging extends range to 175 nm; optional accessories permit use as direct reader or scanning ~ spectrometer Baird-Atomic Spectro- Inc..met 1000 125 Middlesex Turnpike, Bedford. Mass. 01730, U.S.A. Warner Drive, Spectro- Springwood vac-1000 Industrial Estate, Rayne Road, Braintree, Essex CM7 7YL, England Spectro- met I 1 DR 30 0.6 or 0.3 210-590 1.0 m 1.0 m 2.0 m 2.0 m Arc or spark; m odu lar Compact, low-cost direct reader with minimum air-conditioning requirements; manual master monitor t o check slit alignment Ferrous metals (except determination of S) using C 193.1 nm, P 214.9 nm in 2nd order; non-ferrous metals.oils DR 30 0.6 or 0.3 173-767 Arc or spark; modular Compact, low-cost direct reader with minimum air-conditioning requirements; logarithmic read-out; manual master monitor t o check slit alignment; dual stand option Automatic optical servo monitor continuously maintains correct slit alignment; logarithmic read-out; manual master monitor to check slit alignment; temperature- compensated fixed focal length; dual stands for Ar and air available As Spectromet I I ; all photomultipliers in vacuum Ferrous and non-ferrous metals, including C, S, and P DR 0.294 190432 0.59 190-363 As Spectromet 1000 60 Ail direct-reader applications above 190 nm Spectro- vac I1 DR 60 0.29 173-432 As Spectromet 1 om All direct-reader applications, including C, P, and S 1.5 m General Spectrographic analysis General spectrographic analysis Jarre I I-As h 78-090 Phot.- 1.1 or 0.54 420-970 Div.. Fisher 21 0-485 Scientific CO., 590 Lincoln St., 70-310 Phot.- 1.0 or 0.24, 180-3000 Waltham, depending 180-1500 Mass. 02154, upon grating 180-750 3.4 m U.S.A. Versatile instrument, particularly suitable for measuring transient spectra 75-150 Phot. - 4.4 to 1.1 20-6000 3.2 to 0.8 1.6 to 0.4 0.75 m 1.0 m or 2.0 rn 0.75 m 0.75 m 96-750 DR Up to 50 0.54 168-500 96-785 DR Up t o 5 0 0.54 168-50 (continued) * New equipment since pubhcation of volume 7 Most metallurgical analysesTable 2.5A CO M M ERCIALLY AVAIL ABLE EM TSSI 0 N SP ECTRO METERS - con tin u e d Suitable for spectro- .scopic investigations rather than for analytical applications Reciprocal Supplier Model Type c ~ ~ q ; ~ f l l s :lp;;;iFi ~~~~~~~~h Type of source Special features Applications 1.5 m As above Choice of 2 gratings All direct-reader a p p I i c a t ions above 190 nm 0.56 or 0.28 200-800 or 0.34 to 0.17 200-510 or 19woo 190-250 (continued) 1500 OR Up to60 70-314 DR 30 As 70-310 As 70-310 3.4 m As above Easy interchange to As for Model 1500 photographic (70-310) version W2-484 Scan.- 1.5-120 Depends on 0.275 m Supplied by 25 rnm wide focal plane With detector arrays grating user at exit 1 *a2485 Scan. - 1.5-120 As above 0.275 m As above Easily Interchangeable *82-486 gratings *82-487 82-410 Scan.- 1.6 and 3.3 200-900 0.25 m Tungsten deuterium 82-020 Scan. - Depends on Depends on 0.5 m Supplied grating grating by user Various scanning spectrometers I J 75-150 Scan. - As above As above 0.75 m As above 1.0 m 2.0 m Labtest 310 DR 60 0.56 190-900 1.5 m ‘Transource’ Wavelength in first order; Ferrous and non-ferrous Equipment Co., 1 high-voltage- CRT; teletype printer or alloys 11828 La Granae V-25 DR 40 0.67 170-550 1 .O m triggered computer readout systems; As above Ave ., discharge. Low- dual air/inert gas and Los Angeles, Calif. 90025, 2100 DR 30 0.46 188-455 1.0 m d.c. arc U .S.A. J voltage-triggered solution excitation stand 1 (As above 0.52 170-900 2.0 m ICP source for General purposes 71 DR 74 solution analysis M.B.L.E., Philips DR 60 0.55 or 0.46 170430 1.5 m Triggered Optional dual air/Ar Rue des PV 8300 (80 lines) capacitor excitation stand; choice Deux-Gares 80, Vacuum !ischarge; of program ma ble B-1070, Monoalternance’ calculator and computer Brussels, discharges up to configurations with dual Belgium 500 Hz; d.c.arc; cassettes on floppy d i y s ; intermittent rapid printer VDU d.c.arc; glow extension options discharge, hollow cathode Philips Philips DR 40 Analytical PV 8350 Dept.,, Vacuum Pye Unicam Ltd.. 0.46 177410 1 m As for PV 8300 Integrated spectrometer system including source and readout options as for PV 8300 Steels, iron, non-ferrous metals, and non- conductive powders; air stand for oils, d.c.arc, etc. Steels, iron, non-ferrous metals, non-conductive powdersYork Street, Philips Cambridge, PV 8210 CB1 2PX, Air England Phllips PV 8250 Air DR 60 0.55 or 0.28 190-700 1.5 m As for PV 8300 Wavelength range covered (50 lines) plus ICP in 1st order; remote- con t r o I led roving detect or; external excitation; rotrode and inert atmosphere facilities; readout as PV 8300 DR 40 0.695 or 0.35 190-610 1 m As for PV 8210 Integrated spectrometer 0.59 or 0.35 190-531 system with built-in source 0.92 or 0.46 190-820 and readout options as for 0.46 or 0.23 190-410 PV 8300 All direct-reader analyses above 190 nm, particularly non-ferrous metals, solutions, oils, and non-conductive powders As for PV 8210 Rank Hilger, Westwood Industrial Estate, Margate, Kent, CT9 4JL, England E l 000 Pol yvac DR 60 0.293-1.155 156-880 1.5 m Various, including Solid state electronics: high-repetition computer control available.condensed arc, Dual gratings give 12 ICP, GDL standard systems to select optimum dispersion and wavelength coverage. Special grating if required. dual spark stands E960 DR 36 0.546 or 0.741 174.0-447.7 0.75 m As El000 Curved entrance and exit slits; solid-state electron'ics.Computer control available; air or inert gas discharge stands Monospek DR Slngle D-400 0.66-15.7 200-22000 1.0 m As selected Curved or straight entrance and exit slits: scanning wavelength can be read t o 0.01 nm from digital counter; wavelength accuracy F 0.1 nm with 1200 line per rnrn grating Ferrous and non-ferrous alloys; geological samples; wear metals in oils Ferrous and non-ferrous alloys; wear metals in oils Scanning monochromator of particular use for monitoring and examination of plasma sources Spectrametrics AE 2 Phot., 1 0.06 190-800 0.75 m Plasma jet Inc., DR 204 Andover St., Andover, DR10 DR 20 0.06 190-800 Plasma jet Mass. 01810, (inter- U.S.A. changeable cassettes) Routine analysis Routine quantitative and a hiph temperature Optimized AE system using a high-dispersion, high-energy-throug hput echelle spectrometer plasma jet excitation source Techmation E S 9 Phot.- 0.06 190-800 0.75 m Plasma jet, flame, Built-in computer Ltd.. or arc stand Way, Edgware, M iddlesex, (variable HA8 8JP. wavelength) 58-Ed gware RS1 DR 1 0.06 190-3-800 0.75 m Plasma jet, flame, or arc stand Qualitative and semi- quantitative analysis; spectroscopic research England * New equipment since publication of Volume 7Table 2.5A COMMERCIALLY AVAILABLE EMISSTON SPECTROMETERS- continued Applications Spex Industries 1870 Scan./ - 1.6 1751280 0.5 m - Multi-purpose unit Routine analysis Inc., Phot. 3880 Park Ave., Metuchen, 1702 Scan./ - 1.1 N.J. 08840. Phot. 175-1500 0.75 m - Research - U.S.A.- - 1704 Scan./ - 0.6 175-1500 1.0 rn Phot. Glen Creston, 16 Carlisle Rd., 1802 Scan./ - 0.8 180-1500 1.0 m London Phot. NW9 OHL, England *1269 Scan. - 0.65 180-1500 1.26 m Research - Direct reading Routine analysis accessory available Very high resolution Research VEB Carl Zeiss Jena, 69 Jena, Carl-Zeiss Str. 1. German Democratic Republic Carl Zeiss Sc'ie n t i fic Instruments Ltd., PO Box 43. 2 Eistree Way, Boreharn Wood, Herts, WD6 1NH England PGS-2 Phot. - 0.74 or 0.37 200-2800 2.075 m Arc or spark Atlas for spectra evaluation: 0.76 wide choice of precision diffraction gratings; high resolving power; dispersion doubling or multiplying as required; automatic transport of cassette; wavelength scale for quick orientation of the user within the spectra; wide range of accessories available including LMA-10 laser-microspectral analyser Q-24 Phot.- 0.76 210-550 0.54 m Arc or spark High light intensity, (at 250 nm) variable slit width ranging from 0.001-0.3 mm; built-in * New equipment since publication of volume 7 slit shutter and step filter; wavelength scale for quick orientation; atlas for spectra evaluation; full range of accessories available including LMA-10 General spectrographic analysis: also examina- tion of line profiles, hyperfine structure, etc.General spectrographic analysis b 3 3 5. i2 b 2cTable 2.SB COMMERCIALLY AVAILABLE PLASMA SPECTROMETERS Operating Special features No of $ ~ ~ ~ , ~ ~ $ Wavelength Focal Suppl'er Type Chainels nm per mm range/nm length Outpul freq- M Hz power uency/ Appllcatlonr Applied Research Quanto- DR 48 0.695 or 0.347 190-610 1.0 m 2 kW r.t.Full computer controlled Laboratories Ltd., meter 0.930 or 0.465 190-820 r.t. ICP to provide direct Wingate Road, B4000/ICP or 0.310 concentration print-out: Luton, Beds., LU4 8PU, including dual cassette: England dual floppy discs; visual full range of options display units; fast printers, remote terminals and computer links etc.All ferrous and non- ferrous powders including slags, rocks, soils etc; particularly suited to the analysis of highly alloyed materials; computer options availa- able to allow incorpora- tion into plant systems EDT Research Ltd., MPS 600 DR 6 or 8 14 Trading Estate Road, London, NWlO 7LU 19&500 0.5 m 20-150 W MIP 2450 Multi-channel concave High absolute senstivity grating polychromator with pg detection limits fitted with quartz refractor for several elements plate: data presentation: sequential through channels: optional printer or punch tape units; simultaneous multi- element analysis for pl sample solutions: fully programmable system for desolvation, asking and vaporization of samples Jarre I I-As h 96975 DR Up to 0.54 168-500 Div., Fisher 50 Scientific Co., 590 Lincoln St., Waltham, 06988 DR Up to 0.54 168-500 Mass. 02154, 50 U.S.A. V. A. Howe & Co. Ltd., 88 Peterborough Road, London SW6 3EP 0.75 m 2 kW r.t. r.f. ICP 0.75 m Computer controlled; variable channel; concentration print-out Corn pu ter controlled ; N+1 channel scanning monochromator attach- ment; spectrum shifter attachment for automatic background correction: special K and Li channels: Data Management System All solutions Simultaneous multi- element determinations of trace elements down to ppb levels in aqueous and organic solutions Jobin-Yvon, JY 38P Scan.Division d ' Instruments, 16-18 Rue du Canal, 91160 Long jurneau , France (continued) 1 .o 175-750 1.0 m 1.5-2.5 27.12 Czerny-Turner mono- Metals and alloys, rare scanning, 0.005 or 0.125 minerals, water pol- nm per step at 0.3 to 3500 lutants, pharmaceutical nm per min with recorder control, biomedical synchronisation; computer analysis, blood and system serum kW chromator; wavelength earths, soils and r.t.ICP P wlTable 2.5B COMMERCIALLY AVAILABLE PLASMA SPECTROMETERS - continued e m Generator Reciprocal Supplier Model Type c::;,$ “,P;;;iFi 2;; output Operating freq- Special features power uency/ MHz Applications ( continued) EDT Research Ltd., 14, Trading Estate Road, London, NWlO 7LU JY 48p DR 48 0.45 at 175450 168-800 1.0 m 1.5-2.5 27.12 Paschen Runge mounting Metals (C, S and P), 0.58 190-590 or 1 m diameter, air or oils, water, soils and 0.69 210-71 0 5.0 kW vacuum, 86 positions of minerals, biomedical 0.80 24W50 r.f.ICP multipliers: fully automatic analysis read-out; computer option Kontron GmbH, 8057 Eching bei Munchen, Oskar-von-M iller Str. 1 , West Germany tPlasma- Scan. 0.8-1.6 150-450 0.6 m 4 kW 27.12 spec or optional System 190-700 t o 7 kW 3 r.t. ICP General purpose Plasma- DR Up to 0.23-0.46 187455 1.0m 4 kW 27.12 General purpose spec 30 optional System t o 7 kW 4 r.f.ICP Labtest Equipment Plasma- Scan. - - 250850 0.35 m 2 kW Czerny-Turner General purposes co., scan monochromator: 11828 La Grange 700 microprocessor control: Avenue, enclosed sample pumping Los Angeles, system; computer Calif. 90025 read-out system. U.S.A. Q M.B.L.E., Philips DR 60 0.55 or 0.28 190-700 1.0 rn r.f. Wavelength range covered All direct reader analyses Rue des Deux PV 8210 ( 50 in 1st order: remote above 190 nm, particu- larly, non-ferrous metals, Gares 8, lines) B-1070 read-out by printer, solutions, oils and Brussels, Belgium teletype or digital non-conductive powders 5 b .z controlled rovi.ng detector; computer systems 2.Phi lips Analytical Dept., Pye Unicam Ltd., York Street. Philips DR 40 0.695 or 0.35 19&610 1.0 m PV 8250 0.59 or 0.35 190531 Air 0.92 or 0.46 190-820 0.46 or 0.23 190410 Cam bridge; CB1 2PX, Philips DR 40 0.46 177-410 1 . 0 m England PV 8350 Vacuum r.f. lnteorated soectrometer As for PV 8210 system with ’built-in source and readout options as for PV 8210 J f 3 r.f. Integrated spec?rometer Steels, iron, non-ferrous g system including source metals, non-conductive and readout options as powders for PV 8210 8Rank Hilger, El000 DR 60 0.29S1.155 159.6864.3 1.5rn Westwood Polyvac Industrial Estate, Margate, Kent, CT9 4JL, England €960 DR 36 0.546-0.741 174.0447.7 0.75 m Ferrous and non-ferrous ' instrument; dual gratings alloys, geological give 7 systems samples, wear metals in 3 oils r.f.Curved entrance and exit Ferrous and non-ferrous ' slits; solid-state alloys, wear metals in 3 2 electronics or computer oils controlled: air or vacuum 2 G r.f.Computor controlled Specirametrics Spectra- Inc., span I l l 204 Andover Street, Andover. Mass. 01810, U.S.A. Techmation Ltd., Spectra- 58 Edgeware span I V Way, Edgeware, Midd lesex, HA8 8JP, England Photo. 20 0.06 190400 0.75 rn DR Inter- change- able cassettes plasma Optimized AES system d.c.arc using high-dispersion high-energy throughput echelle grating spectrometer; integral microprocessor High sensitivity even In presence of complex matrix solutions with solid contents up to 20% Routine sequential, quantitative analysis and multi-element analysis Quantitative and qualitative analysis of trace concentrations including refractories and some non-metals t No up to date lnforrnatlon supplled.Table 2.32 COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS Single/ Grating Reciprocal Resolution Wavelength Readout; Supplier Model double Monochromator lines dispersion/ /nm range/nm ex;;;;on Other features beam per mm nm per mm Baird-Atomic Ltd., A5100 Single 0.25 m Czerny- 1200 3.0 0.1 186-860 Warner Drive, Turner Springwood Industrial Estate, Rayne Road, Braintree, Essex CM7 7YL, England Baird-Atomic Inc., A3400 Single 0.25 m Czerny- 632 125 Middlesex Turnplke, Turner Bedford, Mass. 01730, U.S.A. A3600 Single 0.25 m Czerny- Turner 632 6.0 6.0 0.2 lg(r-860 0.2 19&860 Digital; Automatic background correction; 4-lamp turret; x 0.5-40 auto zero: integration; curve correction; Wavelength scan; flame ignition; gas safety devices; lens optics; emission and fluorescence Meter or 4-lamp turret:.auto zero; digital; x25 curve correction: integration; flame ignition: wavelength scan: emission and fluorescence Meter or Integration; flame digi?al; x25 ignition; wavelength scan; emission and fluorescence Beckman Instruments 1233 Double L'ittrow GmbH,t 8 Munich 40. Frankfurter Ring 115, West Germany 1236 Double Littrow Beckrnan-Rl IC Ltd., 1248 Double L'ittrow Turnpike Road, Cressex Industrial Estate, 1272 Double L'ittrow Hlgh Wycombe, Bucks, HP12 3NR, England 1200 2.7 0.2 190-860 Meter; x55 Single- or triple-pass optics: O/O T; abs.or concentration readout 1 2 0 2.7 0.2 190-860 Digital; x 55 As model 1233 1200 2.7 0.2 190-860 Meter; X I 0 Auto zero and calibrate; 1200 2.7 0.2 190-860 Digital: x1Q As model 1248 integration plus curvature correction G CA/McP herson EU 703 Single - Instruments.t 5% Main St:, 'Acton, Mass. 01720, U.S.A. 1180 2.0 0.1 180-1100 Digital Modu!ar AA; flame emission; various detectors and gratings available; convertible to single- or double-beam U.V. spectrometer Hitachi Ltd., 170-10 Single Littrow Nissei Sangyo Co. Ltd.,t Mori 17th Bldg., 26-5 Toranomon, 1 -c home, M inato-ku , Tokyo, Japan 1440 2.25 0.4 190-900 Meter; Single lamp mounting xo.l-1 NZO-air simultaneously, X.l,lO exchanged; concentration Dig I tal ; readout; continuously (optional) variable time constant P 00 bNissei Sangyo, Instruments Inc., 392 Potorero Ave., Sunnyvale, Calif. 94086, U.S.A. Nissei Sangyo GmbH, 4 Dusseldorf, Am Wehrhahn 41, West Germany 170-30 Single Littrow 170-50 Double Littrow 170-70 Double Littrow 1440 1440 1440 2.25 2.25 2.25 0.4 0.1 0.1 190-900 As 170- 190-900 As 170- 0 Concentration readout; time-weighted signal averaging: AAS/AES measurement; auto zero: NzO-air simultaneously exchanged 0 Background correction, channel balance free system, base-line drift correction, curve corrector, time-weighted signal averaging, auto zero 190-900 Met*er/Digital Polarized Zeeman effect: option flameless background correction over the complete 190-900 nm wavelength range: background correction to 7.7 abs.Instrumentation 751 Double, 0.33 m Ebert 1200 2.25 0.04 160-1000 0.01-1UOOX Laboratory Inc., dual (both channels) 68 Jonspin Road, channel Wilmington, Mass. 01887, U.S.A. Instrumentation Laboratory (UK) Ltd., Kelvin Close, Birchwood Science Park, Warrington, Cheshire 180-1000 0.01-1OM1x 551* Double 0.33 m Ebert 1200 2.25 0.04 (continued 1 Microcomputer controlled: calibration curve linear- ized in both channels, using up to 5 siandards: background correction functions in channel A and channel 6 simul- taneously: readout will display A,B A/B or A-8.Automatic gas box is.standard feature: optional 4-lamp turret,wavelength scan, and bu'ilt-in alpha- numeric printer Microcomputer controlled; calibration curve linear- ized using up to 5 standards: memory will store up t o 10 calibration curves simultaneously: video screen displays standard conditions for each element, the working curve, and will show transient signals. Fully automatic fail safe gas box is standard feature: optional background correction, 4-lamp turret, wavelength scan, and alpha-numeric printer t No up t o date information supplied * New equipment since publication of Volume 7 P v3Table 2.K COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS --continued Single/ Grating Reciprocal Resolution Wavelength Readout; beam Der mm nm per mm Supplier Model double Monochromator lines dispersion/ range/nm Other features (continued) 257* Double 0.33 m Ebert 1200 2.25 0.04 180-1Ooo 0.01-looox 157* Single 0.33 m Ebert 1200 251 Double 0.33 m Ebert 1200 151 Single 0.33 m Ebert 1200 2.25 2.25 2.25 0.04 0.04 0.04 180-1000 0.01-1ooux 180-1000 0.01-1OOOX 180-1000 0.01-100(1x Microcomputer controlled; calibration curve linear- ized using 2 standards or 5 standards (optional).Fully automatic gas box is standard feature; optional background correction, 4-lamp turret, wavelength scan and alpha-numeric printer with statistics Microcomputer controlled; calibration curve linear- ized using 2 standard or 5 standards (optional). Fully automatic gas box is standard feature; optional background correction, 4-lamp turret, wavelength scan and alpha-numeric printer with statistics High speed digital elec- tronics; full-time-integra- tion, peak area and peak height; off-line calibration curve correction.Autogasbox is standard feature; optional back- ground correction, 4-lamp turret, wavelength scan High speed digital elec- tronics; full-time-integra- tion, peak area and peak height; off-line calibration curve correction.Autogasbox is standard feature; optional back- ground correction, 4-lamp turret, wavelength scan0.02 193-860 Digital Laminar-flow burner, 3.3 in t egra I g as-fl ow controls ; Turner auto zero; concentration correction; 2-lamp turret Jarrell-Ash Division, Dial Single 0.25 m Czerny- 1180 Fisher Scientific Co., Atom 590 Lincoln Street, I l l Waltham, Mass. 02154, calibration; curvature U.S.A.V. A. Howe & Co. Ltd., 82-810 Double, 0.4 m Ebert 1180 2.08 0.03 190-900 Digital; Laminar-flow burner; 88 Peterborough Road, dual x 25 curvatui e correction; London, SW6 3EP, channel 2-lamp turret Computer-controlled England 0.03 190-900 Digital 82-850 Single 0.4 m Czerny- 1180 2.08 parameters Turner 280 single 0.27 m Littrow 1800 1.6 0.2 190-860 Perkin-Elmer Corp..Main Ave., Norwalk, Conn. 06856, U.S.A. Perkin-Elmer Ltd., Beaconsfield, Bucks. HP9 lQA, England Digital; X 0.01-50 (continued) 380 Double 0.27 m Littrow 1800 560 Double 0.27 m Littrow 1800 1.6 1.6 703 h b l e 0.4 m Czerny- U.V. 280 0.65 Turner vis. 1440 1.3 0.2 0.2 0.03 190-860 Digital; X 0.01-50 190-860 180-440 4W900 Digital; xo.01-loo Digital; x 0.01-1 00 High-energy optical system; microprocessor- controlled; auto zero; auto conc.; auto curve correction with 2 standards: peak height, peak area; integration time selectable from 0.5 to 20 s; flame ignition; optional auto NzO switching; optional burner-head safely interlock; optional deuterium arc background correction As Model 280 but all mirror optics; automatic gain control; auto NzO switching; burner head safety interlock; optional flame and pressure sensing by microco.mputer burner control; optional deuterium arc double- beam background correction As Model 380 but auto curve correction, with up t o 3 standards; statistics; integration time selectable from 0.2 to 60 s As Model 560 but optional 4-speed wavelength drive: no automatic gain control - * New equipment since publication of Volume 7Table 2.5C COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS- continued Single/ Grating Reciprocal Resolution Wavelength Readout; beam oer mm nm Der mm /nm range/nm exE%on Supplier Model double Monochromator lines dispersion/ Other teatures (continued) 5000 Double 0.4 m Czerny- Turner U.V. 280 vis. 1440 0.65 1.3 0.03 170-475 Digital; 17&900 X 0.01-1 00 Completely automated sequential AA system: instrument can analyze up to 6 elements with minimal operator participation; all analytical parameters, including lamp current, wavelength selection, resolution, qas flows, standardization and signal read out can be entered and stored using magnetic cards; doubls-beam background correction for all U.V.and visible viavelenyrhs; when instrument is used i n conjunction with HGASOO it will provide sequential analysis for up t o 6 elements with same analytical ease as with flame Bodenseewerk, 400 Double Perkin-Elmer & Co.GmbH, Postfach 1120, D-7770 Uberlingen, West Germany 410 Double 422 Double 432 Double 0.33 m Czerny- 1800 1.3 0.2 190-860 Turner 0.1 7/ 190-860 '' 0.27 Double Qratlng 2800/ Czerny-Turner 1800 1.6 0.33 m Czerny- 1800 1.3 0.2 190-860 Turner 0.1 7/ 190-860 0.27 Double grating 2800/ Czerny-Turner 1800 1.6 Digital; x 50 and x 0.2 concentration, Auto zero, auto integration, curve correction, BCD outlet, automatic flame ignition As Model 400.but with double-grat ing monochromator As Model 400, but with microcomputer electronic keyboard operation; linearization with up to 3 standards; EIA RS-232C data outlet As Model 420, but with double-grating monochromator Digital Digital Digital Pye Unicam Ltd., SP 191 Single Ebert York Street, Cambridge CB1 12PX, England 1200 3.3 0.2 190-850 Digital; 4-lamp magazine; auto X 0.1-25 zero; integration; curve correction: emissionSP 192 Single Ebert SP 2900 Double Ebert Data Centre - - ,*SP9 Single Ebert - - *SP9 Comp u ter 1200 1200 1200 3.3 3.3 4.7 I 0.2 0.2 0.2 190-850 Digital: X 0.1-25 190-850 Digital; X 1-50 - - 190-850 Digital; X 0.5-25 - - As SP 191, but simultaneous background- $ e facility added 4-lamp magazine; auto zero; integration; curve zi correction, with average .? caiibraiion facility; peak height measurement with 2 timer,peak area; emission; simultaneous 5 3 background correction as accessory Fully microprocessor c1 controlled data process- g.ing by programmable calculator; 3 types of curve correction; statistics; standard additions and other data handling; full calculator ability retained 4-lamp turret; gas control module with full safety interlocks. Deuterium background corrector; scale expansion and curvature correction; burner interlock as standard Curve correction with up 5 standards in fixed or variable ratios; peak height or peak area; full statistics; running mean 2 2 Rank-Hilger, Atomspek Single Czerny-Turner 1200 2.6 0.1 190-850 Digital 6-lamp turret; auto zero Westwood Industrial H 1580 and flame ignition; curve Estate, correction; integration; Ramsgate Road, programmable calculator Margate, Kent, CT9 4JL, England Shimadzu-Seisakusho Ltd.AA-625 Single Czerny-Turner - 1.9 0.2 190-700 Meter or Quantitative flame 14-5 Uchikanda, expand- digital emission; flameless 1-chome, Chiyoda-ku, able to 900 capacity; flow lines for Tokyo, 101, Japan air, C~HZ and NzO (continued) * New equipment since publication of Volume 7 wl wTable 2.32 COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS - continued Singre/ Grating Reciprocal Rerolution Wavelength Readout; Other ieatures range/nm Supplier Model double Monochromator lines dispersion/ beam Der mm nm oer mrn (continued) 190-900 V.A. Howe & Co. Ltd., AA-630 Single Czerny-Turner - 1.9 0.2 88 Peterborough Rd., London, SW6 3EP, England AA-640 Single Czerny-Turner AA-650 Double Czerny-Turner 1200 1.9 1.9 3.2 0.2 190-900 Meter or Quantitative/qualitative digital flame emission; flameless capacity; flow lines for air, Ar, CZHZ, N20, Hz; flame monitor; gas pressure monitor; wavelength drive Meter or Automatic background digital correction; quantitative and qualitative flame emission; flameless capacity; flow lines for air, Ar, C~HZ N20, and H2; flame monitor; gas pressure monitor; wavelength drive; integration Automatic background correction; quantitative and qualitative flame emission; built in peak catcher; flameless capacity: flow lines for air, Ar, C~HZ NZO, and Hz; flame monitor; gas pressure monitor; wavelength drive; integration 190-900 ;deter or digital Varian Techiron Pty., 1100 Single 679 Springvale Road, Mulgrave, Vic. 3170, Australia Varian Assoc. Ltd., AA-275+ Single Instrument Group, 28 Manor Road, Walton on Thames, Surrey, England Varian Instrument Div..AA475* Double 611 Hansen Way, Palo Alto, Calif. 94303, U.S.A. 0.25 m Czerny- 1276 2.8 0.2 185-900 Turner 0.25 m Czerny- 1200 3.3 0.2 185-900 Turner 0.25 m Czerny- 1200 Turner 3.3 0.2 185-900 Meier/Digital 4-lamp turret; auto zero; >( 0.3-50 integration; curve correction; peak reader; f/8 aperture; optional aul om at ic gas- box Digital; Reflective optics with x 0.001-100 quartz overcoat; micro- processor system with three-standard calibra- tion, optional automatic gas control, background correction, 2-lamp turret Digital; Reflective optics with x 0.001-100 quartz overcoat; micro- processor system with ;hree-standard calibra- tion, optional automatic gas control, background correction, 2-lamp turretAA-575 Double 0.25 m Czerny- 1200 Turner AA-775+ Double 0.33 m Czerny- 1800 Turner AA-6 Single; 0.51 m Ebert dual channel 638 3.3 1.6 3.3 0.2 0.05 0.05 185400 Digital; Reflective optics with cl x 0.001-100 quartz overcoat; fully > microprocessor controlled, three-standard $ calibration, optional automatic gas control, background corrector and !? 4-lamp turret 3 c r" microprocessor controlled, five-standard 2 calibration with statistics 5 and standard additions ca I I br at i on ; opt i onal automatic gas control, background corrector and 3 185-900 Digital; Reflective optics with xO.001-100 quartz overcoat: fully 2 185-1000 Digital: X 0.3-50 4-lamp turret Modular construction; auto curve correction: f/10 aperture; optional automatic gas-box, simultaneous background corrector, and calculator interface VEB Carl Zeiss Jena, 69 Jena, Carl-Zeiss Str. 1, German Democratic Republic Carl Zeiss Scientific Instruments Ltd . , PO Box 43, 2 Elstree Way, Boreham Wood, Herts, WD6 lNH, England AASl Single 0.50 m Ebert 1300 1.5 - 190-820 Meter; 4ylamp burner: single or x 10 triple pass optics; autozero * New equipment since publication of Volume 7Table 2.5D COMMERCIALLY AVAILABLE ELECTROTHERMAL ATOMIZERS Max.sample Senstivity for lo!? abs. (s.)/pg c u si Special features volume GI Control unit Detection limit (d.l.)/pg Supplier Model Type Baird-Atomic Ltd., A3470 Graphite rod 50 Programmable, d.1. 5 d.1. 60 Fits most AA Warner Drive, dry, ash (2 spectrometers, air cooled, Springwood Industrial Estate, stages), atomize: uses mains power, Rayne Road, max.temp. over inert-gas shielding; Braintree, 3000 "C pyrolytic graphite coating Essex CM7 7YL, England interchange between flame for rods i n situ; rapid and eiecwothermal methods Beckman Instruments GmbH, 1271 8 Munich 40, Frankfurter Ring 115, West Germany Graphite furnace 100 Programmable, d.1. 4 d.1. 10 Water-cooled, inert-gas dry, ash, atomize, (100 # I ) (100 P I ) shielding; safety feature burn off; max.temp. 3100°C for failure of water or purge gas; gas stop; fits Beckman and Pye Unicam instruments Instrumentation Laboratory 555 Graphite furnace 100 Programmable, d.1. 0.8 d.1. 10 Controlled-temperature Inc., six stages, furnace, using feedback 68 Jonspin Road, ramp or step; from a tungsten Wilmington, max. temp.temperature sensor; true Mass. 01887, U.S.A. 3500 "C temperature readout; safety interlock system: Instrumentation Laboratory automatic cell door; (UK) Ltd., automatic cleaning; cell Kelvin Close, pressurization; convenient Birchwood Science Park, solid sampling capacity Warrington, using microboats Cheshire 5 E '1 Jarrell-Ash Division, FLA 100 Graphite furnace 50 Programmable, d.1. 10 d.1. 50 Fits most AA 7 Fisher Scientific Co., dry, ash, atomize; s. 50 s. 50 spectrometers, inert-gas 5' 590 Lincoln Street, ramping and flash shielding, but an air ash 2 b Waltham, atomization possible Mass. 02154, U.S.A. Perkin-Elmer Corp., HGA-400 * Graphite furnace 100 Microprocessor d.1. 2 d.1. 20 High-speed temperature ;in Main Avenue, unit provides up to sensor accessory permits 2 Norwalk, 8 steps of rapid heating to k Conn. 06856, controlled heating; temperature between % U.S.A. temperature, ramp 600 and 3000 OC for 2 2 2 time, hold time, optimal atomization: 0Perkin-Elmer Ltd., Beaconsfield, Bucks, HP9 lQA, England gas and other furnace and spectrophotometer control functions are programmed by direct keyboard entry. Digital displays provide readout of tempera- ture, time and programme status HGA-BOO Graphite furnace 100 Microprocessor unit provides up to 9 steps of con- trolled heating; temperature, ramp time, gas and other furnace and spectrophotometer control functions are programmed for each step by direct keyboard entry; dig,ital displays provide readout of temperature, time and programme status.Up to 6 complete pro- grammes can be stored and recalled at the touch of one key AS-1 furnace auto-sampler available for automatic insertion of up to 30 samples into the HGA with automatic triggering of HGA and instrument read cycle, for unattended operation d.1. 2 d.1. 20 Furnace control programmes for up to 6 different elements may be stored in 6 programme memories; when used in combination with the AS-1 furnace auto-sampler and the model 5000 AA spectrophotometer, up to 30 samples may be analyzed for up to 6 elements each without operator attention; programme parameters for more than 6 elements can be stored on magnetic cards and recalled with the push of one button; the optical temperature sensor and digital gas flow control for 2 different gases add to the versatility of the furnace programme Bodenseewerk HGA-500 Graphite furnace 100 Microcomputer s. 4 s. 30 Fits Perkin-Elmer and Zeiss Perkin-Elmer 8 Co. GmbH, controlled up to d.1. 0.5 d.1. 5 AA spectrophotometers; Postfach 1120, nine program steps water-cooled, inert gas D-7770 Uberlingen, for drying, ashing, shielding, safety features West Germany sample pretreat- for failure of water purge gas or tube break; ram or stepwise increase oP isothermal phase in each of the steps; recorder 2nd peak reader control in each step preselectable; gas stop or mini flow selectable; temperature controlled maximum power heating for atomization ment, atomize, tube clean, tube blank etc; max. temp. temperature plus 3000 "C ( continued ) * New equipment since publication of volume 7v, Table 2.5D COMMERCTALLY AVAILABLE ELECYTROTHERMAL ATOMIZERS--continued 00 Supplier Senstivity for 10/0 abs. (s.)/pg cu Si Model Type M;;zt;n$e Contra, unit Detection limit (d.l.)/pg Special features (continued) A S 1 Auto sampler for 100 Automatic as with as with Fits all Perkin-Elmer AA graphite furnace sampling of up t o HGASOO HGA-500 spectrophotometers with 30 samples once or HGA up to 9 times each Fits all Perkin-Elmer AA \A$ spectrophotometers MHS-1 MercuryjHydride 50 ml System with (H9) system automatic 5. 5 ng programming for d.1. 1 ng 2 ng trace determination of Hg, As, Se, Sb, Te, Bi, Sn Pye Unicam Ltd., SP9-01 Graphite furnace 50 Programmable, s. 44 York Street, dry, ash, atomize, Cambridge, CB1 PPX, tube clean, tube England blank, with cancel and delay stages; max. temp. 3000 C SP9 Video Graphite tube Furnace * furnace SP9 Furnace* Graphite tube furnace SP9 Furnace Autosampler * - Water-cooled, inert-gas shielding, safety feature for failure of water, tube life #indicator and remote recorder control for 1, 2, 3, or all phases 50 6 phases each s. 3 s. 25 Video display of programmable to d.1. 2 d.1. 15 parameters and status; 3000 "C; linear or storage of 9 furnace non-linear ramp on programs; gas stop on each phase; 9 ramp all phases; built-in rates; temperature Autosampler controls or voltage control 50 4 phases each programmable t o 3000 "C; 9 ramp rates between phases 1 and 2; temperature or voltage control 40 Automatic sampling of 38 samples and 2 wash positions. Selectable number of readings per sample Rank Hilger, H1475 Graphite furnace 100 Programmable, Westwood Industrial Estate, dry, ash, wait, Ramsgate Road, atomize; max. Margate. Kent, CT9 4JL, temp. 2600 "C England s. 25 Selectable autozero and s. 3 d.1. 2 d.1. 15 gas stop; fault indication and interlocks; digital display of remaining time $ a s -. - Fits all Pye Unicam 5 after last sample 3 ? spectrophotometers; cup identification; wash system interlock; automatic stop k s. 50 - Water-cooled,inert-gas $ shielding, background correction when fitted to 2 Atomspek H 1551 2 G LaShimadzu-Seisakusho Ltd., GFAZ Graphite furnace 50 Programmable, 5 1 4 5 Uchikanda, dry, ash, atomize; 1-chome, Chiyoda-ku, Tokyo, 101, Japan max. temp. 3000 O C V. A. Howe & Co. Ltd., 88 Peterborough Road, London, SW6 3EP, England - Current stabilized t o obtain 3 reproducible results 3 !? 3 2 Varian Techtron Pty. Ltd., CRA 90 Graphite furnace 25 Programmable, 4 679 Springvale Road, (graphite tube), dry, ash, atom ze; Mulgrave, Vic. 3170, (threaded max. temp. 3000 C Australia graphite tube), (graphite cup) 80 Fils most AA spectrometers, water- cooled, inert-gas shielding and hydrogen flame option; automatic ramp- hold atomization; pyrolytic graphite coating on cup 2nd tubes * New equipment since publication of volume 7

ISSN:0306-1353    

DOI:10.1039/AA9780800031

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

- Methodology 3.1 NEW METHODS 3.1.1 Introduction This section describes novel methods of analysis that are considered to be of sufficient general interest to merit discussion here as well as in the appropriate section on applications. The section also includes papers by workers who have made a detailed study of experimental parameters of widespread relevance. 3.1.2 Sample Preparation Techn'iques Various methods that minimize the time spent in sample preparation have been proposed.The direct analysis of suspensions of finely ground samples (ARAAS, 1977, 7, 23) has many advantages, such as speed, simplicity and low blanks, and has been used for the direct analysis of Cay Fe, Na, Ni and Pb in coal slurries ground to <325 mesh (50). Calibration using aqueous solutions could not be used however, and it was essential to use previously analysed slurrics for calibration.Others workers (539) found that wet ashing with HF/ HNO, /HClO, was preferable to high-temperature dry ashing or low-temperature plasma ashing for the analysis of coal and coke. Losses of Zn were observed with the dry ashing methods. Hernandez-Mendez and co-workers determined Zn in lubricating oils (372), Cu and Fe in benzene (998) and Pb in petrol (7319) by emulsification of the hydrophobic phase into water.A small volume of the sample was shaken with water in the presence of suitable non-ionic detergents, which resulted in the formation of a stable emulsion. The appreciable volatility of lead tetra-alkyls precluded the use of aqueous solutions for calibration and it was essential t o use standardized petrol samples.Wet crshing of biological samples can be time-consuming and a multisample pressure digestion unit that allowed 12 samples t o be digested simultaneously has been described by Stoeppler and Backhaus (1465). Williams (I. Food Technol., 1978, 13, 3167') developed a pressure digestion method for the analysis of Fe, Pb and Sn in canned foods, in which disposable polystyrene containers were used, having polythene screw caps that acted as pressure release valves.The digestions were carried out at 70 "C with either €€NO, or HCl/H,O,. A particular advantage of the method was that many digestions could be carried out simultaneously. Enzymatic digestion of fruit juices was found to give com- pounds that were readily volatilized during the dry ashing stage(s) of ETA (99) (see also ARAAS, 1976, 6 , 156).A simple procedure has been devised by Davis and co-workers (3152) f o r the analysis of Ca and Mg in animal and vegetable tissue. The samples were placed in a vortex mixer and hcated with 1M NaOH at 75 OC in polystyrene tubes €or 5 min. Lanthanum EDTA was then added and the resulting solution was analysed for Ca and Mg in an air/C,H, flame.Good agreement with conventional wet or dry ashing techniques was obtained. Th- technique would not be suitable for trace level measurements of other elements because of significant background absorption from the 1M NaOW. A novel but rather involved volatilization method for the determination of Pb in plant tissue has been reported (68).The sample was heated in an 0, atmosphere in order to oxidize it. Any resulting lead oxide was then reduced in a H, atmosphere at a high tempera- ture and the resulting Pb vapour condensed on a cool surface and dissolved in HNO, prior 6162 Analytical Atomic Spectroscopy to determination. Considerable care must be exercised to avoid the mixing of 0, and H, at high temperatures in glass apparatus! A rapid, simple and virtually universal tcchnique for the dissolution of ores, sinters, slags and ferro-alloys has been described (130) that involves fusing with Na,O, or Na,O,/Na,CO, and treatment of the melt with water.No loss of As, P, Pb or Zn was observed. The rapid analysis of toxic metals in sewage sludges is of growing importance with the increase in disposal of sludge to the land.Various rapid wet digestion methods for sludges have been recommended (1071, 1072, 1092, and T. D. Rees and J. Hilton, Lab. Pract., 1978, 27, 291). It is now generally agreed that time-consuming conventional procedures involving €€N03/HC10, or HNO,/H,SO, are not necessary for this type of analysis; howcver, for soil analysis Scott and Thomas (922).recommended an HF/HClO, digestion and obtained better recoveries than with a HClO,/HNO,/H,SO, digestion or a fusion with Na,CO,. It is not usual practice to oxidize materials containing organic matter with HC10, in the absence of HNO, because of the risk of violent explosion. Four wet digestion methods were examined (1389) for the extraction of metals from aquatic sediments without significant attack on the silica matrix, and it was concluded that digestion with 0.5M HC1 was the most satisfactory.Scott (534) has shown that the widely held view that Cr can readily be volatilized as CrO,Cl, from HNO,/HClO, digestions of sediment samples is wrong. The poor Cr recoveries were shown to be due to adsorption of Cr onto the siliceous residue. Price (80) has reviewed the AAS analysis of micro-samples with special reference to siliceous materials (see also ARAAS, 1977, 7 , 119) and shown that an HF/HCl/HNO, pressure digestion, with sub- sequent addition of H,BO, and further heating is the best method available for a wide range of materials.With the increasing cost of labour some quite complex methods are now being auto- mated and a prime example of this is the automated digestion and extraction system for the determination of trace metals in foodstuffs that has been described by Stockwell et al.(420). It was based on a continuous flow system and consisted of five component modules - sample introduction, digestion with H,SO, /HNO, /H,O, at 400 "C, neutralization, chelation with DDC, and extraction into heptan-2-one. The only manual sample prepara- tion was weighing 5-10 g of the freeze-dried sample into a polythene bag, adding 30 ml of 12M H,SO, and heating at 60 "C.followed by homogenization of the sample. A somewhat similar type of system for the determination of As and Hg in fish tissues has been reported by Agemian et aZ. (639, 1401) (see also ARAAS, 1975, 5, Ref. 185). A semi-automated tech- nique for the separation and determination of Ba and Sr in surface waters using ion exchange has been developed (10). Forty samples could be prepared in 90min and analysed within a further 20 min. Two novel methods for the rapid breakdown of organo-mercury compounds have been reported. Farey et al. (529) added 2ml of a solution containing 0.27% m/V KBrO, and 1% m / V KBr to 50ml of the acidified sample.The liberated Br, resulted in the rapid breakdown of methylmercury and phenylmercury compounds and also prevented loss of Hg on to the walls of the sample container. Shimomura e l aZ. (137'6) showed that if Fe(III) was added to an acidified sample, the addition of NaBH, solution resulted in break- down of organo-mercury compounds.Freeze drying has been shown to produce no signifi- cant loss of Hg from fish or mussel samples (571). The effect of adsorption of the Hg vapour on the inner walls of the apparatus after liberation from the analyte solution in the Hg cold-vapour technique has been determined (616). A comparison of NaBH, and SnCl, for the generation of HgO (ARAAS, 1976, 6, Ref. 512) showed that both reagents had specific disadvantages (93).In the presence of I-, SnCl, gave poor recoveries, while in the presence of Ni, NaBH, gave poor recoveries. It has been reported {417) that by filteringChapter 3: Methodology 63 a 2% m/Y NaBH, solution containing a small amount of KOH through a 0.45pm membrane filter the useful life of the solution was increased €rom 1 day to several weeks.Various methods of sample preparation have been found to increase the sensitivity and minimize inter-element effects when using hydride generation techniques (19S, 887, 1342). Co-precipitation of As with Fe(OH), (551, 1075) was recommended for the determination of As in natural waters. The addition of HF to the sample solution has been found to minimize inter-element effects from Nb, Si, Ti and W in the determination of As in metal A novel solid sampling technique for determining elements in singte algal cells has been developed by Lorch (1097).The freeze-dried algae were spread on paraffin on a microscope slide using a Pt wire, then, after viewing the slide through a microscope, single cells were collected in a lop1 drop of water hanging from a plastic pipette tip.The drop containing the single cell was then placed into an ETA device. The analysis of trace impurities in elemental boron has been simplified by volatilization of the boron using acetic anhydride and methanol (48). The method was rapid and resulted in lower residual boron concentrations than were obtained in alternative methods. The advantages of metallo-immunoossay have been stressed by Cais and nine co-workers (7).Specially prepared metallo-antigens were allowed to react with antibodies and after separa- tion of the resulting metallo-antigen-antibody complex, the metal content of the bound or free phase was monitored using ETA techniques. A significant advantage is that the method does not require the use of radioactive isotopes; however at present the technique is some- what less sensitive that radio-imniunoassay. The preservation of samples, the choice of sample container and sample trcatment are prime considerations in ultra-trace analysis (1 385, 1386, 1390) and often insufficient comideration is given to these aspects of the work.Filtration (< 1 pm), acidification and deep freezing was found to preserve sea-water samples for the determination of Cu and Fe (238).Moody and Lindstrom (632) have evaluated impurity levels in a wide range of plastic sample containers, using various analytical techniques, and have proposed methods for the preparation of sample containers for ultra-trace analysis. Linear polyethylene sample con- tainers and acidification of the sample to pH<1.5 with HNO, have again been recom- mended for the preservation of trace metals in natural waters (see also ARAAS, 1976, 6, 65; G.E. Batley and D. Gardner, Water Res., 1977, 11, 745). alloys (34). Other references of interest - Hg in coal: 1398. Microdetermination of trace elements in biological material: 1471. S in steel, S , emission following H,S generation: 770. Wet and dry ashing of grasses: 1469. 3.1.3 Pre-concentration Techniques 3.Z.3.Z Solvent Extraction. Reports of new reagents for the solvent extraction of trace elements continue to appear. The reviewer cannot help feeling that more effort should be made to reduce the lack of agreement between different laboratories using “accepted” solvent-extraction methods for the analysis of typical samples. This would be more helpful than the further proliferation of new exotic reagents that are often only used to extract synthetic solutions.The mono-octylester of a42 carboxy-anilino) benzylphosphonic acid (1 197) has been used to extract Fe(III), Mn(II) and Zn, and 1 -phenyl-3~methyl-4-benzoyl-5-pyrazolone (1 27’5) has been evaluated for the extraction of Co, Cu, Fe, Mn, Ni and Zn. Problems continue, how- ever, to be experienced in the commonly used APDCIMZBK system; poor stability of the lead and certain other APIX complexes in MIBK has been observed and back extraction64 Analytical Atomic Spectroscopy into acid has been recommended (19, 915, 1169, 1236, 13151). 1,1,2-Trichloro-l,2,2-trifluoro- ethane (Freon T.F.) has been used to extract A P E and DDC metal complexes, followed by back extraction into HNO, (881).Freon T.F. should not be nebulized into a flame. Various solvents and chelating agents for the efficient interference-free extraction of Co and Ni have been examined (538) and the pyridyl-azo-naphthol /CHCI, system was recom- mended for the ETA determination of these elements. Viets (942, 953) has reported the extraction of many metal iodides (Ag, As, Bi, Cd, Cu, Ga, Hg, In, Pb, Pd, Pt, Sb, Sn, Te, TI and Zn) from HCl solutions containing ascorbic acid using ‘AZiquat 336’ (tricaprylmethyl ammonium chloride) dissolved in MTBK.Thc trace metal halides were extracted by exchanging with the chloride ion of the Aliquat 33’6, or as oxonium ion associaticn pairs with the MTBK. For some metals both extraction mechanisms were found to be important. Two more selective methods for the determination of Cr(V1) have been reported; the first relied on the formation of dimercaptomaleonitrile-chromium(V1) complex followed by extraction into MIBK as an ion-pair with tetrabutylammonium ions (54.71, while the other utilised the formation of perchromic acid and rapid extraction into MPBK (232).When Ge was extracted from 8’M HCl into n-butyl ether and the ether layer washed with 12M HC1 a five-fold increase in sensitivity was observed (225).It was shown that the 12M HC1 wash resulted in the formation of GeCl, which was more readily volatilized and atomized than the germanium species extracted from 8M HCl. A combination of solvent extraction and concentration by evaporation has been used by Kasterka et aZ.(75) to determine Bi, Cd, Co, Cu, Fe, Ni, Pb and Zn in natural waters. The metals were extracted into n-amyl acetate using DDC!, followed by a further extraction with 8-hydroxyquinoline; thc combined extracts were then concentrated five fold in :’ rotary evaporator at 30 “C. An unusual solvent extraction application was the determination of orgai.to-silicoizes in sewage studge (1251).Thc sludge was extracted with toluene, the extract evaporated to dryness and redissolved in a small volume of MTBK. The extract was then passed through an activated charcoal column, eluted with MIBK and the Si level in the eluant determined. Cresser (51 3) has written a book entitled ‘Solvent Extraction in Flame Spectroscopic Analysis’. The main part of the book, which cites 795 references, is divided into sections on each of the elements, and this enables the reader to survey rapidly the multitude of possible extraction systems for a given element.APDC/CCl,, Cd in sea-water: 1461. Boron using 2-ethylhexane- 1,3-diol: 36. Tellurium using TOPO/MTBK: 91. Other references of interest - 3.1.3.2 Adsorption Concentration. Horvath and co-workers (40, 700) have used iminodiacetic acid ethyl cellulose to concentrate various metals from ammonium acetate soil extracts.Concentration factors up to 20 times were possible and good separation from the main matrix ions (Ca, Mg and Na) was demonstrated. Controlled-pore glass beads (Bio-Glas-200, mesh size 100-200) were found to be a simple and effective method of preconcentration of trace metals from ‘artificial sea-water’ (1 85).The beads were shaken with the alkaline sample solution for 1-2h, then removed, and extracted with a smnll volume of acid. Recoveries of 90-100% were obtained for Cd and Pb at the 1 pgl-’ level. It should be pointed out that the metals present in many natural water samples exist a s complex species and can behave in a different manner from those present in synthetic solutions.Chapter 3: Methodology 6 5 3.1.4 Indirect Methods The ingenuity of AAS enthusiasts in extending the area of applicability of the technique continucs to astound, D'Alonzo (315) has produced a dissertation on the indirect determina- tion of primary aliphatic and aromatic amides, organo-sulphidcs and polymers using AAS.The indircct dctcrmination of phosphatr: utilisiiig phosphomolybdate formation (see ARAAS, 1971, 1, 50) continucs to be rcported.Phosphate has been determined in saline and non- saline waters (580, 802), rocks (1323, 1324), cast iron (802) and alloys (366). One group has even completed the analysis by monitoring the Mo concentration by ETA (730). This system may soon rival the interference of phosphate on calcium in the air/C,H, flame for the number of papers published! Flame emission methods have been proposcd for vicinal-diols (744) and A1 (916). The former werc determined using Malaprade oxidation to carbonyl compounds, followed by formation of their sulphite addition compounds and then monitoring of the S, emission.Aluminium was determined using a calcium inhibition titration (ARAAS, 1971 1, 265).An indirect AAS method for biuret in fertilizers was compared with the official AOAC method and found to be satisfactory (3773. Fluorine has been determined by monitoring GaF absorption at 21 1.4 nm and AIF absorption at 227.5 nm in flames and ETA devices (1344) (see also ARAAS, 1977', 7, 79))). Boron has been converted to BF, using CaF, and H,SO, and determined by monitoring €30, emission and B F absorption in a N,O/H, flame (237, 1344). 'Aggressive (3'0,' in waters has been determincd by adding Cr;CO, to the sample and determining the increase in dissolved Ca concentration (1 142).Eke and Frank (1 80) ha:Te dcter- mined total organic carbon in aqueous solutions by direct nebulization of the sample into an air/H, flame containing a silver tube.The chemiluminescent emission of the silver 328.3 nm line was monitored, the emission signal being generated by the reaction CH + 0 + Ag -+ CHO + Ag*. The detection limit however was about 1000 pg ml-1 C, which will limit the use of the technique. Indircct AAS methods have also been proposed for anionic and non-anionic detergents (12, 1470), antihistamines (1 1 lo), CS, and dithiocarbamates (9671, ethambutol (406), glycosaminoglycans (592), long-chain primary amines ($559, phenothiazines (8481, sulphate (454, S95), sulphide (973) and U (573). 3.1.5 Nebulization, Vaporization and Atomization The inherently simple discrete-sample nebulization technique (see ARAAS, 1975, 5, 15) has the advantages over conventional ncbulization that only small sample volumes (typically 20-200 pl) are required for each measurement and that solutions containing very high levels of dissolved solids can be nebulized without clogging the burner slot or causing significant memory effccts.Various applications of th:: technique have been describcd (1 1, 699, 7'49, 969, 1001, 1013, 1032). Schleicher and Leighty (124) have developed a commercial ETA auto-sampler based on the work of Matousek (see ARAAS, 1977, 7, 79).The liquid samples are directly nebulized into a heated graphite tube (150 "C) for a fixed time pxiod and the dried sample within the tube is subsequently dry ashed and atomized. The sensitivity was found to be directly proportional to the time of nebulization (for periods of 1-100s).Inter-element effects, however, would be expected to be more sevcre with increased nebulization periods. Various modifications to ICP nebulizers have been made to improve sensitivity and allow nebulization of solutions with a high level of dissolved solids (1406, 1407, 1409, 1410. 1447). Other modifications have bzen made to allow direct nebulization of organic solvents without build-up of carbon on the sample tube tip (1411).Controlling the sample uptal;:: rate of a pneumatic nebulizer with 3 pcristallic puma w;ts found to niinimize th,: cffect of variations in the height of the liquid sample 2nd nlso66 Analytical Atomic Spectroscopy that of acid concentration, when using an ICP (679, 867). The addition of 5% m / V of a non-ionic surfactant to all solutions (86’7) allowed the maximum dissolved solids concentra- tion to be increased from 1 to 3 4 % m/m without clogging of the nebulizer.When the nebulizer tip was silylated, 10% m / m of dissolved solids could be tolerated. Manabe and Homi (1408) have developed a Babington-type nebulizer (see ARAAS, 1975, 5, 15) which can be used for the direct nebulization of HF solutions into an ICP.The use of element-specific spectroscopic detectors for GC ond HPLC i s becoming more widespread (see 1.2.2.3). Numerous types of GC detector have been reported, including microwave photometric devices (56, 60, 61, 156, 173, 10073, MECA devices (6, 896), flame photometric devices (6, 330, 902, 903), a Hg absorption tube (333), a d.c. Ar plasma (909), glow-discharge devices (59, 631), a flame AAS device (155) and an ETA device (6).Hemnann and co-workers (105n have used a flame photometric detector to monitor Br, C1 and I in a HPLC effluent using a Gilbert indium burner (P. T. Gilbert, Anal. Chem., 1966, 38, 1920). A commercial ETA device (323) as well as a flame (1347’) have been coupled to a WPLC instrument fm the detection of organometallic compounds.Koizumi et al. (1011) used a Zeeman-effect AAS instrument to detect various organometallic species in a wide range of solvents; other workers (55) determined various organo-selenium compounds using a similar system. The Zeeman background correction system allowed results to be obtained even though there were very significant background absorption signals. The direct analysis of solids using ETA can result in problems due to light scattering and/or molecular absorption.Van Loon and Radziuk (403) overcame this problem by volatilization of the sample in a graphite furnace followed by atomization of the resulting vapour in a flame. When non-dispersive AFS was employed, simultaneous multi-element analysis of biological, environmental and geological samples was achieved.Fike and Frank (181) have extended their work on the determination of Br and I (see also ARAAS, 1977, 7, 23) by using copper halide formation to determine Cu directly in sheet metals. A standard Beckmann O,/H, burner was fitted with a cylindrical steel chimney with air holes at the base. A lateral slit at the top of the chimney allowed insertion of the sheet metal samples.An entrained air/H,/N, flame was supported on the burner, O.5M HC1 was nebulized and the emission intensity of the 324.7nm Cu line was monitored above the chimney. It was possible to detect Cu levels down to 1% m / m . The AAS determination of phosphorus at the P 213.6 nm non-resonance line using ETA (ARAAS, 1977, 7 , Refs. 81 and 899) would appear to be a useful technique with a detection limit of 0.1-0.5pgml-1 (202, 205, 325, 664, 962, 1027, 1343).The addition of La to all solutions and standards has been found to be beneficial (202, 205, 664, 962). Hanamura (176) has developed a low-power air CMP (see also 1.2.2.4). The minimum power required to sustain the discharge was 250W; this was achieved by inserting a platinum electrode at the base of the discharge.Lead was determined in automobile exhausts, industrial atmospheres and in petrol. For the latter application 5-1Opl of petrol was vaporized in a plastic bag. Other references of interest - Branched capillary nebulization: 1091. Direct analysis of solids by AAS (review): 335. Direct nebulization of metal oxides and sulphides: 131 8. Discharge chamber for AAS: M2. ETA-emission of Ba: 224.Glow-discharge source with resonance detector: 523’. Pulsed atomization: 101 5. Slotted silica tube in flame: 515.Chapter 3: Methodology 67 3.2 ANALYTICAL PARAMETERS 3.2.1 Introduction Good precision of analytical results does not necessarily imply good accuracy and intcr- laboratory comparability exercises or the analysis of CRMs should be carried out on a regular basis by all laboratories.The need for this approach has again been demonstrated by a recent (alarming) study (533) concerned with the analysis of 16 trace metals in natural water by 35 laboratories in 19 countries (see 3.3.2). The accuracy of analytical results can be critically affected by unsuspected interference effects in both OES and AAS, and it is important to stress that these effects can vary from instrument to instrument (e.g., ARAAS, 1976, 6, 12 and ARAAS, 1977, 7, 81).The increasing production and usagz of CRMs should ultimately result in improved accuracy of analysis. 3.2.2 Detection Limits, Precis'ion, and Accuracy An authoritative and comprehensive review of noise and SNR in analytical spectrometry has been produced, in two parts, by Alkemade et al.(1034, 1035). The sources, mathematical representation, and major types of noise in emission and luminescence spectrometry are discussed. In the first part of the paper an extensive treatment of noise and the SNRs of paired readings is given, using the relation between the auto-correlation function and the spectral noise power. The second part gives general expressions for SNRs in spectrometric systems.Ingle and Bower (152) used theoretical equations to study the effect of instrumental variables on SNR in AAS measurements. They found optimum instrumental settings (e.g., slit height and width, flame stoicheiometry, and observation hcight) to vary with analyte concentration. The concept of detection limit is still a much misunderstood one.A statistical trcatment by Boumans (1064) has studied the interrelation between detection limit and limit of identification. It is emphasized that detection limits serve only to differentiatc b-tween true analyte signals and random fluctuations of the blank, while it is the limit of identification which indicates the maximum concentration present that has a stated probability and escapes attention. Greenfield et al.(1453) have emphasized the shortcomings of published detection limits as applied to ICP-OES. The values are only mcaningful if determiiicd in the matrix of interest and under routine experimental conditions. In ordzr to formalize the determination of ICP detection limits, a working party has now been formcd. Weeks et al. (904) studied means of improving detection limits in laser-excited AFS.They found that attention should be given to reducing stray light, the principal source being from the surroundings rather than the flame itself. Illumination of a l a r y r area of the flame also led to improved SNR. Daily (559) studied the effect of statistical and systematic uncertainties on detection limits in laser-excited AFS.Simultaneous multi-element determinations involve a compromise in experimental conditions for determining a miximum number of elements; Seeley et al. (9349 have shown how optimization of parameters during emission spectro- graphy can significantly improve detection limits for selccted groups of elements. A statistical treatment of analytical results by Evans (522) emphasized that all stages of a procedure (i.e., sample preparation, instrumentation, variation in matriccs, variation in analysts, etc.) are important when considering precision and detection limits.In order to ensure accuracy in multi-elcment spcctrography, identical transport, ioniza- tion, and excitation of the sample and reference standard are required. In practice these requirements are difficult to achieve, and Golightly et al. (648') haw studied correlations between measured temperatures, electron prcssures, and matrix composition with a view to improving accuracy.The shapes of malytical curves in flame spectrometry are affccted by incomplcte volatilization of the sample in the flamc. Roos (514) derivcd exprcssi.ons for curve shape and68 Arialytical Atomic Spectroscopy compared the results with those obtained experimentally.Effects of changes in observatior, height and flame temperature on the extent of sample volatilization were outlined. A system that might have potential as an excitation source for spcctrochemical analysis has been studied theoretically by Eckert (1066). A static ICP in a closed tube was assumed to have a known temperature distribution, to be in local thermal equilibrium, and to undergo complete mixing with the vapours of trace analyte elzments. This allowed theoretical detection limits and analytical curves to be calculated. Watters and Norris (1417) used internal standards in ICP-OES to correct for systematic errors caused by drift.The use of a dual-channel atomic absorption spectrometer in con- junction with internal standards has been recommended for certain analyses (729).The role of interlaboratory comparison studies for indicating the precision and accuracy of a technique has been illustrated by Dybczynski et 01. (5339. Results from 315 laboratories in 19 countries for 16 tracc elements in water samples showed good intra-laboratory precision, but a very large spread of results between laboratories indicating generally poor accuracy.To give an indication of the range of results reported, those for Hg ranged from 0.13~3.0 pg 1-1, nominal value 1 pg 1-1, while the Cd results varied from 1.9-9.3 pg l-’, nominal value 4 pg 1-1 (in both cases after rejecting extreme outlying results). However, thc overall mean results by AAS agreed well with neutron activation analysis, demonstrating that the inaccuracies of individual laboratories were not attributable to inherent inaccuracies in either technique.Simplex optimization allows the simultaneous variation of several experimental para- meters in order to obtain improved response from analytical systems; it i s being increasingly used in atomic spectrometry.A review of the technique by Deming and Parker (1070) discusses the basic simplex algorithm, modified algorithms, and analytical applications. Other references of interest - Statistical uncertainties of photon counting measurements: 979. Table of state-of-the-art detection limits with ICPs: 561. Theoretical and experimental factors affecting accuracy and precision: 4’35. 3.2.3 Interferences 3.2.3.1 Plasmas.Olson et al. (113) have studied the effect of widely different concomitant concentrations (Al, Fey K, Na and PO,3-) upon the ultrasonic nebulization /aerosol desolva- tion sample introduction technique. The 16 analyte elements studied showed a 10% change in intensity for molar ratios of 1000 to 1 and up to 50% at molar ratios of 10000 to 1. Optimization of the plasma and nebulizer operating parameters was successful in reducing the depression at the highest molar ratio to less than 15%.Skogerboe and Olson (769) confirmed that the observed depression was due to the formation of larger solid particles when the aerosol was desolvated, causing loss by gravitational settling. Leis et al. (732) have also studied the effects of high concomitant concentrations; in this case the large amounts of Na,B,O, used for fusion of rock samples significantly affected the ncbulization rate.Other references of interest - Assessment of interferences in the analysis of biological materials and soils: 662. Background reduction in TCP using FAAS: 1310. 3.2.3.2 Flames. Stajanovic et al. (1 191) have studied the mechanism of sulphate interferelice in the determination of alkaline-earth metals, using AAS inhibition release titration.A solution of alkaline-earth elements was titrated with a solution of MgSO, while the titrand was aspirated into an air/H, flame. Changes in the Mg absorbance signal werc registeredChapter 3: Methodology 69 and they demonstrated the formation of compounds of constant composition.A similar study of phosphate interference has been made (1190). The N,0/C2H, flame has been recommended for the determination of Cr (71, 1260, 1313). It was found that the addition of various buffers (e.g., NH,Cl, S-hydroxyquinoline, etc.) was not effective in minimizing chemical interference effects in the air/C,H, flame (1260, 1313). Pszonicki and Krupinski (71) made all solutions 2000 pgml-1 with respect to Ca in order to remove chemical interference effects caused by Al, Ba, Co, Cu, Fe, K, La, Mg, Mn, Mo, Nay Ni, Ti and V in the determination of Cr in the N,0/C2H, flame. Sanzolone and Chao (1150) have recommended the use of a fuel rich N,O/C,H, flame for the accurate determination of Mn in geological materials.Yoshimura and Noda (555) described the effect of dispersed carbon black in minimizing interferences caused by phosphate OT fluoride on the atomic absorption signals of Cu, Pb and Zn sprayed as aqueous suspensions of their oxides (ARAAS, 1977, 7 , Ref. 1516). Investigations into the determination of Eu, Gd, La, Nd, Pry Sm and Y have shown that Ce has a considerable enhancement effect; errors arising from this source were prevented by the addition of K (72).The addition of 0.3M NH4C1 to marine leachates has been successful in overcoming serious suppression of the Fe AAS signal in the air/C,H, flame (703). Pereverzeva (1026) has suggested the addition of H3P04 and Al(NO,), as a means of minimizing inter-element effects on Mo in an air/C,H, flame. In the determination of alkaline-earth metals in steels using an air/C,H, flame, it has been found that traces of Fe remaining after solvent extraction caused serious interference in the Sr AAS signal and t o a lesser extent with those of Mg and Ca.The addition of LaCl, overcame the interference from Fe as well as that from PO,3- and SiO,2- (1 239, 1320). The first report on the final results of the activities of the European Community Reference Bureau, Expert Group on 'Drug Interference in Clinical Chemistry' has been published (799) and concentrates on the interference of ascorbic acid on commonly used clinical methods of analysis, including the determination of Ca by FAES.Kometani (I") studied matrix effects in the determinaion of La in barium titanate by the flame emission of Lao. The addition of Al(NO,), has been found to overcome the unexpected interference of W when analysing for K by FES (1230) (ARAAS, 1976, 6, Ref, 66).A collaborative study (R. C. Rooney and J. W. Woolley, Analyst, 1978, 103, 1100) of the apparent inter- ference effects of Ca on the AAS determination of Ba using a N,O/C,H, flame has been carried out. It was concluded that the observed interferences were largely caused by instru- mental artefacts and should be avoidable.One possible cause was overload of the demodu- lator by the intense CaOH emission at the Ba 553.5 nm resonance line wavelength. Solutions containing 10 ,ug ml-1 of Ba and up t o 10000 pg ml-1 of Ca were circulated to several laboratories and absorbance measurements carried out on 15 commercial instruments. Only 5 instruments exhibited negligible interference at the 10 000 p g ml-1 Ca level, while the remainder exhibited signal levels of 0.25-9 times the expected level.Other references of interest - Background absorption effects, Cu in plants: 910. Background absorption Li salts: 1368. Background absorption K salts: 1369. Cu in serum, effect of silicone tubing: 1162. Matrix effects in rock analysis: 348.Mg in nodular iron, interferences in: 1193. Ti in silicate rocks, interferences in: 243. Review of interference effects: 825. Wear metals in lubricating oils, interferences in: 34~7.70 A naly tical A tom ic Spectroscopy 3.2.3.3 Electrothermal Atomization. Newstead et al. (1 378) discussed the relative merits of the various systems for background correction and the conditions relating to optical and electronic alignment.Optimal correction was claimed to be given by systems based on the Zeeman system. In a study of interference effects in furnace AAS, Czobik and Matousek (945) showed that interference in transition-metal chloride systems could often be attributed to spectral overlap between interfering atoms and analyte species and that the addition of acids of high boiling-point restored the response for the systems Ni /CuCl,, Pb /CdCl, and Cu/PbCl,.The use of a short furnace was instrumental in minimizing overlap interferences by sequential volatilization of the various components, but at the expense of poorer detec- tion limits. Several suggestions have been made for the alleviation of interferences in the deter- mination of Pb (399).Manning and Slavin (110, 704) confirmed the results of earlier work by Hodges (ARAAS, 1977, 7 , Ref. 298) with regard to the coating of the graphite tubes with Mo salts with special reference to chloride interference. Organic acids and NH,NO, were found to be useful as matrix modifiers when used in conjunction with Ma coated tubes. The risk of minor explosions should be borne in mind when working with easily oxidizable substances in the presence of NH,NO,.The addition of an excess of a Li salt was found by L'vov (471) to reduce considerably the suppressing effects of chloride on several elements; a theoretical explanation was postulated (see 1.4.3). Langmyhr and Kjuus (892) overcame the problem of chloride interferences in solid samples of bone by repeated evaporations with HNO,. Julsham (6983 reported the suppressing effect of 0.0 1-1 .OM HC10, on the absorbances of 10 elements and suggested removal of the acid by evapora- tion with HNO, in a platinum crucible.Further work on the interference effects of Ca, Mg and Na salts in the determination of Al, Cr, Cu, Mn, Pb and Sb has been reported (638, Maessen et al.(104Q) studied the influence exerted by concomitants on the vaporization and atomization behaviour of Be, Mn and Zn. The vaporization patterns of the test elements were studied during the atomization stage and the variation of the transient absorp- tion signals with time was measured. This very thorough paper draws attention to the lack of knowledge on thermochemical processes in carbon-furnace AAS, even compared to that available for arc emission spectrometry.Other references of interest - 1207). Cd, Cu, Pb and Zn in milk and fruit juice, interferences in: 456. Pb in waters, use of ascorbic acid: 521. Effect of NO,- on the determination of Ni and V: 230. General interference study: 828. Influence of furnace conditions on interference effects: 570.Interference effects in the determination of Cu and Mn: 63'8. Interference effects in the determination of Cu, effect of alkali and alkaline-earth halides and NaClO,: 901. Spectral interferences in the determination of Se: 968. 3.2.3.4 Hydride Generation and Other Techniques. In order to overcome the suppressive effect of metallic ions in the determination of As and Se, Taddia and Kirkbright (735, 893) have described the use of various masking agents (see 1.6.1).For As, thiosemicarbazide and/or 1 ,lo-phenanthroline was successful in minimizing interference from Ni, Pd and Pt; up to 1000-fold weight excess of Ni and 500-fold excesses of Pd and Pt could be tolerated. For Se, only Te(1V) was found to be successful, with up to a 200-fold excess of Cu or a 500-fold excess of Ni, Pd or Pt being tolerable.It should be noted that relatively large amounts of toxic H,Te will be liberated when using this procedure.Chapter 3: Methodology 71 Other references of interest - Interference effects in a capillary arc excitation source: 223. Spectrographic analysis of petroleum, interferences in: 757. Spectrographic analysis of steel, interferences in: 11 84. 3.3 STANDARDS AND STANDARDIZATION 3.3.1 Standards In an attempt to overcome the shortage of standards for OW in the geological field, a series of synthetic reference materials has been prepared using the co-precipitated gel tech- nique (415). Major and trace elements can be covered by this technique. Knott et al. (1312) described the preparation of calibration standards for OES and XRF in which a series of lithium/lanthanum tetraborate beads were made from pure oxide materials.During the past 13 years 65 standard reference water samples have been prepared by the U.S. Ge- logical Survey (9373.; the stability of Al, As, Ca, Co, Hg, Na, Pb and Se over several years has been confirmed. The samples have been the subject of inter-laboratory method studies.A number of RMs have been prepared, specifically for industrial health applications (171), consisting of 3 membrane filters for Be, Cd, Mn, Pb, Zn and quartz, and 2 freeze-dried urine samples containing low and elevated levels of F and Hg. Suggestions have been invited by the National Bureau of Standards (U.S.A.) for further RMs in this field. Earlier problems in the preparation of air particulate RMs with an air filter calibration facility appear to have been overcome and 4 sets of standard filters have been prepared (189).Dokiya et (11. (1266) have reported on the preparation of wet fish RMs taking advantage of the homogaous elemental distribution in shark meat. The Comite Inter-Institutes (R. C. Daniel, Euroanalysis 111, paper 2639 has prepared a set of 12 RMs for plant analysis con- sisting of tree leaves analysed for B, Ca, C1, Cu, Fe, K, Mg, Mn, N, P, S and Zn.Also of interest to environmentalists is a soil RM. The report (R. Dybczynski, Euroanalysis 111, paper 327’) contained data on the preparation and standardization of ‘Soil-5’, and a com- parison of the analytical methods used. The importance of reference materials and methods has been emphasized again by Unano and Gravatt (3’55, 1090) and Michaelis (357, 13’3).McLauchlan (358) has reviewed current demands and availability of metallurgical products within the EEC. Pending the publication of a world wide directory of certified reference material (CRM) sources, Cox and Ridsdale (J. D. Cox and P. D. Ridsdale, National Physical Laboratory (UK) Report, Chem. 93, October 197’83 have produced a guide to CRMs available from suppliers in the UK covering the following use categories: geology, physical chemistry, nuclear science, environmental science, ferrous metal analysis, non-ferrous metal analysis, polymer science, glass, ceramic and refractory sciences, food and medical sciences, haematology and clinical chemistry, physics and engineering.Jecko and Ridsdale (G. Jecko and P. D. Ridsdale, Eurostandards of Steel Furnace Dusts. Gemtondards Newsl., 1978, 2, 23) have reported the availability of two Eurostandard samples of furnace dust intended primarily for pollution control analysis. Information on 22 major and trace elements was given. Analytical data for 6 South African rock reference samples, ranging from acid to ultra basic types, covering minor and trace elements determined since the samples were first issued in 1972 has been presented by Steele et al.(T. W. Steele, A. Wilson, R. Goudvis, P. J. Ellis and A. J. Radford, Trace Element Data (1966-77) for the 6 NIMROC Reference Samples, Geostmdards Newsl., 1978, 2, 71; NIM Report No. 1351). A comprehensive report describing the preparation, properties and analysis f o r certification of metal dccanoate reference materials for use in the determination of low concentrations of metals in organic materials, e.g., oils, fuels, lubricants, foodstuffs, bio- logical components, has been published by the NPL (National Physical Laboratory (UK)72 Analytical Atomic Spectroscopy Report, Chem. 87, July 1978). It is expected that a major application of this type of calibrant will be in the 'Spectrometric Oils Analysis Program' (SOAP) for monitoring the levels of wear metals in engine oils.Other references of interest - Certification of RMs using ICP: 160. Filter-paper standards for the preparation of standard solutions: 1379. Japanese tea leaves as an RM: 1384. Mixing of solid RMs to produce additional standards: 188.Tests for homogeneity of RMs: 375. 3.3.2 Standardization A reference method for the determination of Ni in urine and serum (463) with preliminary wet-ashing and solvent-extraction steps has been developed following a collaborative study of the various stages of the method with the aid of a 63Ni tracer. Adams et al. (1153) have confirmed that the best results for Ni in urine were obtained using the same preliminary treatment as above and that direct ETA methods gave low results.Rcsults from 2 surveys, involving 7 and 10 laboratories, were reported in this valuable reference paper. Results of an inter-laboratory trial of a reference method for Ca in serum were given by Brown (1306). A method for the determination of Sn in feeds has been subjected to a collaborative study in which dibutyl tin dilaurate was extracted into CHC1, and finally aspirated in methanol (1261).The average recovery f o r 8 laboratories was 98.3% with an RSD of 0.058. The BB Research Centre has published a method for the determination of Cd, Hg, Pb and S'b in single-cell protein (71 8), which has been adopted by the European Community Reference Bureau for certification of a RM protein.The Analytical Methods Committee (Chemical Society, UK) has reported on an inter-laboratory study of a FAAS procedure for the determination of Fe in ammonium sulphate, aluminium sulphate and disodium tetraborate (528). Dybczynski and co-workers (53'3) have made an intercomparison test on the determina- tion of 16 trace elements by 35 laboratories in 19 countries.A concentrated solution in 1M HNO,, that initially had to be diluted 400 times to produce a simulated water sample, was circulated. The results demonstrated good precision from most of the laboratories, but the accuracy was very poor for a number of elements. For instance, the nominal concentrations of Bay Cd and Pb were 32, 4 and 16 ngml-1 respectively; however, the range of concent- trations found after statistical rejection of outliers was 511015, 1.9-9.3' and 12.7-49.7 ng ml-1, respectively, These results demonstrate that setting international statutory limits for various elements in waters is fraught with difficulies.A tentative FAAS method for Ca in waters and sewage effluents (1232) used La to overcome interferences in the air/C,H, flame.Other references of interest - Calibration and sample handling for ETA: 129. Collaborative study As and Se in foods: 1265. Comparison of methods for the determination of Cu in plant tissues: 443. Determination of W: 1460. Internal standards in alloy analysis by OES: 1382. Multi-element analysis of serum by ICP: 1419. Pb in milk by AAS and ASV: 1218.Pb in plants: 1219. Simultaneous determination of Cd, Cu, Pb and Zn in food products: 459. Standardization of AAS analytical procedures: 101 4. Trace metals, comparison of XRF, neutron activation and AAS: 812, 128i7, 1328. Zn in serum: 1151.Chapter 3: Methodology 73 Table 3.3A SPECTROGRAPHIC STANDARDS Aluminium Company of America, Alcoa Technical Center, Alcoa Center, Pennsylvania 15069, U.S.A.X Apex Smelting Co., 6700 Grant Akenue, Cleveland, Ohio 44105. U.S.A. X X X ~~ ~ BNF Metals Technology Centre, Grove Laboratories, Wantage, Oxon. OX12 9BJ, England Bundesanstalt fur Materialprufung (BAM), 1 Berlin 45. Unter den Eichen 87, Germany Bureau of Analysed Samples Ltd., Newham Hall, Newby, Middlesbrough, Cleveland TS8 9EA, England X Denchworth Road, x x x x X x x x x x x x x x x CKD Research Institute, Na Harfe 7, 190 02 Praha, Czechoslovakia x x X Comite de liaison des Industries de metaux Ron-ferraux de la Communaute Europeenne, Boulevard de Berlaimont, 1000 Brussels, Belgium X ~~ Willan Metals Ltd., Poplar Way, Catcliffe, Rotherham S60 5RL South Yorkshire, England x x x x x Johnson Matthey Chemicals Ltd., London EClP lAE, England 74 Hatton Garden, ‘ S pect ro me1 ’@ powders ‘Specpure’@ metals x x x x x x x x x x x x x MBH Analytical Ltd., Station House, Potters Bar, Herts.EN6 lAL, England Office Materials, of Standard Reference x x x x x X x x National Bureau of Standards, Washington, D.C. 20234, U.S.A. Pechiney,23 Rue Balzac, Paris 8e, France Various other metals, including high-purity metals x Soex Industries Inc..x x P:O. Box 798, Metuchen, N.J. 08840, U.S.A. (Glen Creston, 16 Carlisle Road, London NW9 OHL, England) X X X x Zinc & Alliages, 34 Rue Collange, 92307 Lavallois-Perret, France X74 Analytical Atomic Spectroscopy Table 3.31B SPECTROGRAPHIC GRAPHITE ELECTRODES 1 Baird-Atomic, Inc., 125 Middlesex Turnpike, Bedford, Mass. 01 730, USA. 2 Carbon Products Division, Union Carbide Corp., 270 Park Avenue, New York, N.Y. 10017, U.S.A. (ARL Ltd., Wingate Road, Luton, Beds., England) 3 Labtest Equipment Co., 11828 La Grange Avenue, Los Angeles, Calif. 90025, U.S.A. 4 Johnson Matthey Chemicals Ltd., 7'4 Hatton Garden, London EC1P IAE, England 5 Le Carbone (GB) Ltd., Portslade, Sussex, England 6 Le Carbone Lorraine, 45 Rue des Acacias, 75821 Paris, France 7 Jarrell-Ash, 590 Lincoln Street, Waltham, Mass. 021 54, U.S.A. 8 Zebac Inc., P.O. Box 345, Bevea, Ohio 44017, U.S.A. 9 Ringsdofie-Werke GmbH, 53 Bonn-Bad Godesberg, West Germany (Mining & Chemical Products Ltd., Alperton, Wembley, Middlesex HA0 4PE, England) 10 Spex Industries, Inc., 3'880 Park Avenue, Metuchen, N.J. 081S4t3, USA. (Glen Creston, 16 Carlisle Road, London W 9 O'HL, England) 11 Ultra Carbon Corp., P.O.Box 747, Bay City, Mich. 4870.6, U.S.A. (Heyden & Son Ltd., Spectrum House, Alderton Crescent, London NW4, England) Table 3.3C STANDARD METAL SOLUTIONS (MS) AND REAGENTS (R) FOR AAS 1 2 3 4 5 6 7 8 9 10 11 12 13 Aldrich Chemical Co., Inc., !940 W. St. Paul Avenue, Milwaukee, Wis. 53233, U.S.A. (R) J. T. Baker Chemical Co., 222 Red School Lane, Phillipsburg, N.J. 08865, U.S.A. (MS, R) Barnes Engineering Co., 30 Commerce Road, Stamford, Conn. 06902, U.S.A. (MS) BDH Chemicals Ltd., Poole, Dorset BH12 4"N, England (MS, R) Bio-Rad Laboratories, 2200 Wright Avenue, Richmond, Calif. 94804, U.S.A. (MS) Carlo Erba, Divisione Chimica Industriale, Via C. Imbonati 24, 20.159 Milano, Italy Eastman Organic Chemicals, Eastman Kodak Co., 343 State Street, Rochester, N.Y. 14650, USA. (R) Fisons Scientific Apparatus Ltd., Bishop Meadow Road, Loughborough, Leics. LEll ORG, England (MS, R) Harleco, Div. of American Hospital Supply Corp., 60th and Woodland Avenues, Philadelphia, Pa. 1914'31, USA. (MS) Hopkin & Williams Ltd., P.O. Box 1, Romford, Essex RM1 lHA, England (MS, R) V. A. Howe & Co. Ltd., 88 Peterborough Road, London SW6 3EP, England (MS) Instrumentation Labora'tory Inc., 11 3 HartweU Avenue, Lexington, Mass. 02173, USA. (MS) Johnson Matthey Chemicals Ltd., 74 Hatton Garden, London EClP IAE, England (R) (MS)Chapter 3: Methodology 75 14 Koch-Light Laboratories Ltd., Colnbrook, Bucks., England (R) (Anderson & Co. Ltd., Battlebudge House, 87-95 Tooley Street, London E l , England) 15 May & Baker Ltd., Dagenham, Essex RMlO 7xS, England (R) 16 E. Merck, D 61 Darms'tadt, West Germany (R) 17 Spex Industries Inc., 3880 Park Avenue, Metuchen, N.J. 08840, U.S.A. (MS) 18 ALFA Division, Ventron Corp., 152 Andover Street, Danvers, Mass. 01923, U.S.A. (MS). (Glen Creston, 16 Carlisle Road, London NW9 OHL, England) Table 3.31) ORGANOMETALLIC STANDARDS 10 11 12 13 14 15 16 17 Angstrom Inc., P.O. Box 2418, Belleville, Mich. 481 11 , U.S.A. Baird-Atomic Inc., 125 Middlesex Turnpike, Bedford, Mass. 01 730, U.S.A. J. T. Baker Chemical Co., 222 Red School Lane, Phillipsburg, N.J. 08865, U.S.A. BDH Chemicals Ltd., Poole, Dorset BH12 4NN, England Burt and Harvey Ltd., Brettenham House, Lancaster Place, Strand, London WC2, England Carlo Erba, Divisione Chemica Industriale, Via C. Imbonati 24, 20159 Milano, Italy Conostan Div., Continental O'il Co., P.O. Drawer 1267, Ponca City, Okla, W601, U.S.A. Durham Raw Materials Ltd., 1-4 Great Tower Street, London EC3R 5AB, England Eastman Organic Chemicals, Eastman Kodak Co., 343 State Street, Rochester, N.Y. 14650, U.S.A. Hopkin and Williams L'td., P.O. Box 1, Romford, Essex RMl IHA, England E. Merck, D 61 Darmstadt, West Germany MBH Analytical Ltd., Station House, Potters Bar, Herts. EN6 IAL, England Division of Chemical Standards, National Physical Laboratory, Teddington, Middlesex TW11 0,LW England National Spectrographic Laboratories Inc., 19500 South Miles Road, Cleveland, Ohio 44128, U.S.A. Office of Standard Reference Materials, National Bureau of Standards, Washington, D.C. 20234, U.S.A. Research Organic/ Inorganic Chemical Corp., 1 1686 Sheldon Street, Sun Valley, Calif. 91 352, U.S.A. ALFA Division, Ventron Corp., 152 Andover Street, Danvers, Mass. 01923, U.S.A. (Glen Creston, 16 Carlisle Road, London NW9 OHL, England)

ISSN:0306-1353    

DOI:10.1039/AA9780800061

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

CHAPTER 4 Applications 4.1 CHEMICALS 4.1.1 Petroleum and Petroleum Products This year there has been an increase in the number of papers dealing with applications of plasma emission spectroscopy. A review of the use of atomic spectroscopy in the petroleum industry has been presented by Buell (1 107). 4.1.1.1 Petroleum. Hendrick and Eastwood (169) have applied the technique of d.c. plasma emission to the determination of V/Ni ratios in weathered oils, after dilution of the sample with xylene.The same solvent was chosen by Ward (162) and Carr (159) to dilute petroleum samples prior to ICP analysis. A detailed study of the applicability of an ICP system to the determination of trace elements in oil matrices has been undertaken by Peterson (581). Similarly, Merryfield and Loyd (1431) used an ICP for the analysis of wear metals and the characterization of crude oils and feedstock.Grizzle et al. (584) have critically examined the available atomic absorption metlzods for the determination of Ni and V in crude oils, They concluded that dilution with solvent followed by FAAS or direct ETA were unsatisfactory, but that wet-ashing followed by FAAS or dilution followed by ETA gave reliable and reproducible results.The advantages of the N,O/H, flame for use with organic solvents in petroleum analysis were described by Lukasiewicz (63) (see ARAAS, 1W7, 7, Ref. 1212). An indirect method for the determination of organic sulphide in shale oil has been described (973). The sulphide was treated with metaperiodate to give a sulphoxide and the iodate. The iodate was then quantitatively precipitated by the addition of excess of Ag, and the Ag determined by FAAS after redissolution in ammonia solution. 4.1.1.2 Lubricating Oils. Navarro et al (372) have described a technique for the determina- tion of Zn in lubricating oils. The oil was shaken with an emulsifying agent, diluted with water and the Zn determined by comparison with aqueous standards (see ARAAS, 1975, 5, 57).Analytical results for the wear metal content in lubricating oils are known to be dependent on particle size. A method, for the determination of Mo in lubricating oils, based on treatment of the sample with a HF/HNO, mixture, was reported by Saba (9381) to be independent of particle size. Kapoor et al. (34'73 investigated the interference of the additive elements Ba, P and Zn on the determination of wear metals.They reported significant effects in the determination of Ag, Mg and Pb. Kahn and Pau (834) have demonstrated the utility of a two-channel AAS instrument where the wear metal analytical work load i s high. The use of C o as an internal standard in the determination of wear metals by ICP has been described by Andrews et al.(164). 4.1.1.3 Gasoline. A technique based on emulsion formation, similar to that proposed for lubricating oils (see 4.1.1.2), has been shown to be applicable to the determination of Pb in gasoline by FAAS (739). Aqueous standard calibration was not possible, due to sensitivity variations, and diluted standard leaded gasolines were used for this purpose.By interfacing a d.c. plasma emission spectrometer to a GC instrument, Uden et al. (909) determined methylcyclopentadienylmanganese tricarbonyl in gasoline. The determination of Mn by direct aspiration into a N,O/H, flame has been recommended by Lukasiewicz et al. (1283).78 Analytical Atomic Spectroscopy 4.1.2 Chemicals and Miscellaneous Applications 4.1.2.1 Sanzple Preparation.To determine P in alkyl phenyl phosphite, Vigler and co- workers (664) found it necessary to ash the sample prior to ETA-AAS analysis. Ediger et al. (2085) have ddmonstrated that a wide range of F compounds gave similar responses in the graphite furnace when La(NO,), was added. This compound also permitted sample pre-treatment, at elevated temperatures, to be performed in the atomizer without loss of P.The determination of Pb in high chloride matrices by ETA is known to be subject to interference. Manning and Slavin (913) proposed a method of overcoming this problem by coating the furnace with Mo and adding NH,NO, to samples as a matrix modifier, A detection limit of 2Qpg Pb was reported. A method for the determination of mercury in cylinder gases, by AAS, was described by Dittrich et al.(989). The Hg was adsorbed onto a gold wire at 100°C, subsequently removed by rapid heating to 500 OC, and swept into an absorption cell in a stream of Ar. Burns and co-workers (7143 have proposed a method for the decomposition o€ Si containing organoimercurial samples prior to Hg determination by cold-vapour AAS. The sample was decomposed in a PTFE pressure vessel with HNO,/H,SO,, treated with KMnO,, K,S,O, and hydroxylamine hydrochloride and the Hg generated using SnCl,.An IUPAC review (3'9) has described the methods available for the separation and analysis of trace elements in high-purity mineral acids. Sample preparation techniques for the determination of the hydride forming elements were discussed by Watson (1 342).Wet oxidation is normally best for organic samples and alkaline fusion followed by dissolution for inorganic samples. A procedure for the determination of traces of Cu, Fe, Mo, V and Zn in TiCl,, by FAAS, has been proposed by Orlova et al. (267). After dissolution in HC1 the trace elements were extracted with irioctylamine in toluene. Wieteska and co-workers (70) extracted trace elements from high-purity LiH by conversion to the chloride and complexation with &hydroxyquinoline in CHC1, / isopentyl alcohol.An improved method of preconcentration of trace impurities in high-purity elemental boron, prior to spectro- graphic analysis, has been described by Inlow (4'8). The boron was volatilized from an acetic anhydride-methanol mixture by heating.The preconcentration and analysis of trace elements in high-purity strontium and barium nitrates and chlorides has been described by Jackwerth and Willmer (1039). After dissolution, the strontium or barium was precipitated by evaporation as the nitrate and the trace elements, still in solution, determined by FAAS using discrete-sample nebulization. 4.1.2.2 Atomic Absorption Spectroscopy.A number of papers have appeared by Dittrich and co-workers (423, 424 1040) dealing with the analysis of A111 BV semi-conductors, principally Gap, GaAs and InAs, by ETA-AAS. It was established that when a chloride matrix was employed the formation of gaseous diatomic molecules caused signal depression. Investigation of molecular spectra in the region 19&313y> nm indicated that a HNO, sample dissolution could be successfully employed.The determination of In in gallium, gallium phosphide and gallium arsenide and Ga in indium arsenide was achieved with limits of detection of 45 pg Ga and 35 pg In. Strecker et al. (105) have reported that Cu and Fe can be determined in acrylamide solution by direct injection of the sample into a graphite tube furnace.Results compared favourably with a more conventional ashing procedure, followed by FAAS or ICP-OES, and the method was considerably faster. The direct determination of Pb in plastics has been proposed by Girgis-Takla and Chroneos (419) using a carbon cup atomizer. Careful control of the pre-atomization treatment of various plastics, and calibration by standard addition from aqueous solution was claimed to produce results in agreement with a wet-oxidation /extraction /ETA procedure.Chapter 4: Applications 79 The determination of trace elements in brine by AAS is a difficult but necessary pro- cedure in the caustic/chlorine industry. Harrington et al.(94) have described methods including dilution / solvent extraction, hydride and cold-vapour generation for FAAS and ETA, for the determination of 20 of the most commonly required elements.Slyudkin (476) has reported sensitivity changes in the determination of Pt by FAAS when complexed with various amino acids. It was claimed that the sensitivity depended on the nature of the amino acids, the manner in which the Pt was complexed (chelate or monodentate liquid) and on the cis or trans nature of the complex. 4.1.2.3 A tomic Emission Spectroscopy. Golembeski and Lynch (1 12) reported a purpose- built inductively coupled plasma instrument for the determination of trace elements in highly radioactive samples. The high sensitivity obtained allowed much smaller samples to be taken than was possible with other methods. The determination of B, C, H, I, P, S and Si in organic compounds by ICP was described by Windsor et al.(7’84). Samples were vaporized prior to introduction into the plasma and detection limits ranged from 0.6mg for P to 250ng for S. Sample vaporization from a heated Pt boat was used by Hobbs (173) to introduce samples into an MIP for organic micro-analysis. Bromine, C , C1, D, F, H, I, N, 0, P and S were determined simultaneously.A d.c. Ar plasma coupled to a HPLC has been used for the characterization of Cry Cu, and Ni organometallic species. An improved nebulizer was claimed to overcome carbon build up at the electrodes (1400). Mehs and Niemczyk (653) have advocated the use of the hollow-cathode discharge as an emission source for the determination of non-metals, such as As and Se, in environmental samples.The highly energetic source was claimed to excite these elements efficiently, while reducing volatility problems. Similarly, Devyatykh (272) determined impurity elements in TiCl, after separation by vacuum distillation. The bulk analysis of nickel-chromium, phosphorus-silica and silicon-aluminium serni- conductor thin-film materials, using d.c. arc Om, has been described by Hogrefe and Lowry (7$2).The samples were vacuum deposited on to graphite electrodes and the elements measured by comparing the intensity ratios of atomic lines of two elements in the standards and in the samples. For an explanation of the Tables in this Chapter (4.1-4.8), see ARAAS, 1977, 7 , 77.00 Table 4.1A PETROLEUM AND PETROLEUM PRODUCTS 0 Element X/nm Matrix Concentration Tech.Sample treatment Atomization Rd. form Mn 279.8 Gasoline Up to 180 pg/ml E L (as MMT) Mn - Gasoline - A L Mo - Used engine lubricating Trace levels A L Ni - Oil spills Trace levels E L oils Ni - Crude oils UP t o 15 pg/g A L P P Pb S S 213.6 Gasotine - Gasoline - Gasoline - Crude oils (light fractions) 328.1 Shale oil (Ag) 1-10 pg/ml A L From 20 ng (absolute, A L for 90 pl sample) 20-600 pg/ml A L (as tetra-alkyl lead) - E G Trace levels A L GC/OES method for determination of methylcyclopentadienyl-Mn- tricarbonyl (MMT) None Shake with small addition of HF/HNO, and dilute Dilute with xylene.Calibrate by standard addition method. (Rapid method for determination of V/Ni ratios i n weathered oil spills) Comparison of four methods: (A) Dilute with organic solvent (flame) (B) Wet-ash and redissolve (flame) (C) As (A), (flameless) ( D ) Direct analysis (flameless) Absorb sample on Conostan Mg standard (5000 pg/g) + conc.H,SO,. Heat t o fuming and ignite at 650 "C. Dissolve residue (Mg,P,O,) in 1:l HNO,, dilute t o volume and atomize aliquot i n furnace at 2700 'C None, but pre-treat furnace with La(NO,), solution Shake with emulsifying agent (Brij-30 f Tween-80) in H,O, to give final dilution x 50 GC/flame photometric detector system.Column filled with 15% #l#ll-oxydi- propionitrile on Chromosorb W 80/100 used to analyse pyrolysis gasoline and model mixtures Treat with Na metaperiodate to oxidize S to sulphoxides and add AgNO, t o precipitate Ag iodate formed In reaction. Dissolve i n NH,OH and measure Ag P D.c.argon p,lasma F N,O/H, F - P D.c. argon plasma F - Graphite furnace Graphite furnace (HGA-2100) Graphite furn.ace (HGA-2100) F - F - F Air/C,H, 901 1283 931 169 584 664 962 739 ? 5. 5 s 973 % % 2 2 iis E 452 ii' hn V - Oil spills Trace levels E V - Lubricating oils - A V - Crude oils V - Heavy oils Zn - Lubricating oils 0.07-0.1 5% A Various Various Various Various - Petroleum materials - - Engine oils Trace levels - Crude oils: fuel oil; - - Used motor oil Trace levels gasoline - Used oils Trace lsvels E A, E E Various - Petroleum products Trace levels E, F (10) Various - Fuel oils, wear oils pg/g levels E (9) L L L L L L L L L L L L See Ni, ref. 169 P D.c. argon 169 Dilute (1:lO) with MlBK before Graphite furnace 511 5 combustion (Description of modifications t o standard Wickbold combustion apparatus) plasma G f? b % See Ni, ref. 584 F - 584 3 Graphite furnace Dksolve in THF and aspirate. F Add 40-60 YO MlBK to increase sensitivity Emulsify 0.1 g sample in 100 ml H,O by shaking in the presence of 2 ml 10% solution of Emulsifier MS.12 + 5 mi 4% solution of polyethylene glycol nonylphenyl ether. Calibrate with aqueous standards F System for the direct determination of non-refractory elements by FAAS and AES Application of computer-controlled F slew-scan atomic emission/fluorescence spectrometer Dilute ( x 10) with xylene P F Dilute (1 + 9) with organic solvent P F standard.(Comparison of FAAS, ICP and XRF methods) Evaluation of Co as internal standard for wear-metal determination. Ag, Ba, Cr, Cu, Fe, Mg, Mn, Ti, V-good: B, Be, Cd, Mo, Pb, Si, Zn - moderate; Al, Na, Ni, Sn - poor Fuels - none F Oils - dilute ( x 10) with xylene Dilute ( x 10) with xylene.Results given P for Fe, Ni, V, Zn, Mn in fuel oil and Al, Cu, Fe, Cr, Mn, Si in wear oil containing 10 mg/l Co as internal P N20/H2 63 + aspirated solvent d 153 I CP 162 I CP 163 Air/C,H, N,O/C,H, I CP 164 Air/C,H, 150 N,0/C2H2 ICP 159Table 4.1A PETROLEUM AND PETROLEUM PRODUCTS-contirtued ~~ ~~ ~ Element X/nm Matrix Concentration Tech. *na'yte form Sample treatment Atomization Ret.Various - Used oils (7) Trace levels A L Study of interferences by Zn, P, Ba additives on AAS determination of Fe, Cu, Ni, Cr, Mg, Ag, Pb in used lubricating oils L, G (A) For Ca, Mg dilute with light petroleum and apply directly t o carbon-rod furnace (B) For Sb, Sn, Pb generate metal hydride and pass to tube adaptor fitted to same furnace P - 347 51 0 51 2 581 757 758 834 1107 1119 1325 1363 1431 Various - Lubricating oils - (5) A Graphite furnace - Lubricating oils 5-50 E S L S S L L L L L L Mix sample with G%03, char gently and ash at 550 "C.Mix residue (1:l) with LiF-graphite buffer (1:9) - Evaporate on.graphite powder, at 220 "C Evaporate on. graphite powder A 12 A d.c. - Oils - Petroleum Trace levels Trace levels E E E A A, E A A A P ICP A - Various Various Various - Petroleum Trace levels A Double plasma arc F - - Lubricating oils Trace levels Application of double-channel FAAS (Ag, Al, Cr, Cu, Fe) Review of applications of atomic spectroscopy Extract with DDC/MIBK or complex with 8-hydroxyq uinoline Review (10 refs.) Pattern-recognition method, based on levels of Cu, Fe, Pb, Co, V, Cr, Mn, Mo, Ni and Ag Various Various (5) - Petroleum products A, F - mg/l levels Various - Glycol formulations F - Various Various (10) - Petroleum products - Oil spills (in.seawater) Graphite furnace Graphite furnace (HGA-2100) - Trace levels Various - Oils Trace levels E P ICP3 Table 4.1 B CHEMICALS AND MISCELLANEOUS MATERIALS h _ _ ~ ~ ~ _ _ ~ ~ ~~ ___ G Element X/nm Matrix Concentration Tech- Analyte Sample treatment Atomization Ref. 2 form -4 As 197.2 As - Au 242.8 Ba 553.6 Be 313.1 Cd 228.8 Cd Cd c o c u c u - - 324.7 324.7 327.4 Phosphoric acid Silicon semi-conductors Industrial solutions Parenteral drugs Industrial solutions Dyestuffs, antioxidants (for drugs, foodstuffs) Hig h-alp ha (U, Np, Pu) solutions Semi-conductors Spent zinc electrolyte Dyestuffs, antioxidants Acrylamide solutions 0.2-1.2 pg/ml From 0.1 ng (absolute) Trace levels From 5 pg/a (flame) or from 0.2 pg/g (flameless) Trace levels - From 5 ps/g (flame) or from 0.2 pg/g (flameless) pg/g levels (0.03-1 0.9) A A A A E A A A A A A, E L L L L L L L L L L L Reduce t o A s ( l l l ) with KI and add NaBH,, t o generate ASH, After anodic oxidation of Si surface, dissolve oxide film with HF - Dilute and inject directly.Match standards for sample matrix agents e.g., NaHSO,, NaCl I f high levels of Fe and other elements present, add Sr as reference element (Sr 407.7 nm) (A) Wet-ash with H,SO, an.d dissolve (B) Dissolve i n HNO, or C,H,OH in HNO, F N,/H, 637 Q Graphite furnace 1129 b 8.F Air/C,H, 260 9 Graphite furnace 537 @ ( H G A-2 1 00, CRA-90) S Aerosol- 225 spark method F Air/C,H, 44 Graphite furnace Separate U, Np and Pu by extraction F - 839 with tributyl phosphate in paraffin solvent. Determine Cd in residue Prepare solutions in HNO, Graphite furnace 1040 Comparison of colorimetric and F - 593 FAAS methods See Cd, ref. 44 F Air/C,H, 44 Graphite furnace Dry in Pt crucible, ash and dissolve Graphite furnace 105 Use direct injection for furnace method F Air/C,H, in acid. (FAAS and ICP methods) (HGA-2100) P ICP cc, wTable 4.1 B CHEMICALS AND MiSCELLANEOUS MATERIALS-CO~~~~ZLM~ Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. form c u 324.7 Brazing fumes c u P P Fe Fe Fe Fe Ga Hg 324.7 Precipitated chalk - Metal fluorides 529.3 Powders (CaF) 248.3 Acrylamide solutions - Poly(carbon monofluoride) - Ammonium sulphate; Aluminium sulphate; Borax - Polyesters 294.3 Indium arsenide - Organo-Hg compounds containing Si - A A A From 0.002% E pg/g levels A, E (0.1-0.7) Trace levels A - A Trace levels A L L L S L S L L, s L L, G Collect sample, from 100 I of air, on Sympor 4 filter (0.85 /I pore diam), dissolve in HNO,/H,O, and dilute to 100 ml.For Cu, adjust 20 ml aliquot to pH 5.3 with NH,OH, add Na acetate and extract with l,l,l- tr i fl u or o-bmet hy I hept ane-2,4- dione into C6H6. Back-extract Cu into aqueous phase with HNO, Dissolve in dilute HCI Indirect method, using suppression (of Mg) or enhancement (of Ti, Zr) produced by F ion Grind to 1-5 p size and dilute 1:l with CaCO,.Blow powder into arc and measure CaF (529.3 nm) against CaO (549.8 nm) as internal standard See Cu, ref. 105 Inter-laboratory study. (Chemical Society, Analytical Methods Committee) (A) Direct analysis of solid (B) Dissolve in ketone solvent (C) Ash and re-dissolve in acid Dissolve i n 1:l HCI/HNO,.Dilute and take 10 pI sample Digest with HNO,/H,SO, in. PTFE pressure vessel. Oxidize overnight with KMnO, + K,S,O, add NH,OH.HCI and reduce with SnCI, F Air/C,H, 588 F - 854 F - 825 A 22A d.c. 1277 Graphite furnace 105 F Air/C,H, P ICP Graphite furnace 218 F - 528 2 (HGA-2100) $ 2. 5 s 2 s Graphite furnace 728 Graphite furnace 424 %' Cold vapour 714 r, d 3Hg - Gases ( e .g . Ar. 0,) 3.3-60 ng (absolute) - Organic materiais - Hg Hg - Miscellaneous materials - In 303.9 Semi-conductors 2.7-20 pg/g (Gal (Gap) 0.55-15 &g/g 0.55-15 pg/g (GaAs) K -- Caus:ic alkali mixtlrres - Mn - Semi-conductors N 388.4 Gallium phosphide (CN band) or arsenide Na Na NI Ni P - 0.01-1 Yo - Caustic alkali mixtures - 589.0 Strontium phosphate 0.06% level - Poly( carbon Trace levels - Organic complexes 2-8 mg/l 213.6 Aqueous solutions 0-40 mg/l monofluoride) (in extract) A G Pass through tube containing Au wire Cold vapour 989 $ P - 1C'O 5 +g at 100 "C.Release absorbed Hg by rapid heating to 500 "C - - E A G Prepare acid digest, reduce with SnCI,, Cold vapour 1285 co!lec: on Au-trap and re-heat to release Hg A L See Ga, ref. 424, and also "Various," ref. 423 b Y? 2 Graphite furnace 424 2 9 F;; -. Method covers determination of metallic K and Na, in mixtures with KOH, NaOH, K,CO, and N%CO,. Measure K (as KOEt) by flame photometry and determine Na by difference from (K + Na) independent determination See Cd, ref. 1040 Mix (1:5) with carbon powder containing 0.5% Sc,O, and excite in argon a?mosphere, with graphite electrodes.Use Sc 390.7 nm as internal standard See K, ref. 440 Precipitate interfering cations by addition of (NH4),HP0, + NH,OH Dissolve in DMF or CH,.CO.C,H, Add 10 000 mg/l of La (as nitrate) F - Graphite furnace A 12 A d.c. F - F - Graphite furnace F Air/C,H, Graphite furnace (HGA-2100) 440 1040 427 440 844 218 308 20500 Table 4.1 B CKEMTCALS AND MISCELLANEOUS MATERIALS-coiztinued o\ Element X/nm Matrix Concentration Tech.Analyte Sample treatment Atomiza!ion Ref. form P Pb Pb Pb Pt Pt S (SO,) S Sb SI Sn Ti V 213.6 Polyester additive - A L Dilute with DMF and add aliquot Graphite furnace 664 (alkyl-phenyl phosphite) 21 7.0 Dyestuffs, antioxidants 217.0 Plastic containers 283.3 - Chlorides (MgCI,, NaCI) 265.9 Platinum/amino acid - Organo-Si compounds complexes 283.3 Co and Mn salts (Pb) 384 Various materials (water, air, dust, soil) 217.6 Alkaline alcoholic solutions of Sb,O, 251.6 Aluminium gallium arsenide - Polyesters - Polyesters - Polyesters (S, band) From 5 pg/g (flame) or from 0.2 pg/g (flameless) 0.03-1.0 pg/g From 0.1 pg/g 0.3-0.4 yo Trace levels From 25 ng (absolute) Trace levels Trace levels Trace levels A A A A E A E A E A A A L S L L L L L L S L, s L, s L, s to MgO, in presence of H,O,.(HGA-2100) Dry and ignite at 650 "C. Dissolve residue in HNO,, dilute and atomize 25pl aliquot at 2700 "C See Cd, ref. 44 F Air/C,H, Graphite furnace Direct method, using up to 4 mg sample. Pyrolyse at 800 "C and atomize at 1600-1800 "C Add NH,NO, to sample solution, treatment with NH, molybdate in NH,OH solution Results given for both H,O and F Air/C,H, C,H,OH solutions Dissolve in DMF and add Pd as S Rotrode internal standard.(Method for detection of residual H,PtCI, catalyst) Add excess Pb salt solution to F Air/C,H, precipitate PbSO, and determine residual Pb Review of MECA applications for S F H,-based Graphite furnace Graphite furnace and pre-coat furnace tube by (HGA-2200) - F Air/propane Mix with graphite powder.Use A 6 A a.c. Ge 249.8 nm as internal standard See Fe, ref. 728 Graphi?e furnace See Fe, ref. 728 Graphite furnace See Fe, ref. 728 Graphite furnace 44 419 91 3 476 985 454 $ 2. 2 8 2 k 259 Y i -. 38 c, kl x 3 728 728 2 728 2 r, 'JZn Zn Zn Zn Zn Zn CH rad i ca I (indirect) Et ham butol (indirect) Vitamin (indirect) Various 4 2 (7) Various Various (31) 213.8 Dyestuffs, antioxidants 213.9 Hydrochloric acid - Organic complexes 213.9 Brazing fumes 213.8 Acetone - Semi-conductors 338.3 Aqueous solutions (Ag 1 From 0.5 pg/g From 2 pg/ml 0.25-0.75 mg/l (in extract) - 1-100 mg/l - From 0.25% (as ethanol) - Drugs Up to 400 fig/ml 240.7 Vitamin preparations fig/g levels (CO) - Calcium fluoride 0.1-2.5 fig/g (Cd); 5-25 fig/g (CO); 1-25 fig/g (others) - High-purity mineral acids Trace levels - Elemental boron fig/g levels - High-purity lithium hydride Trace levels A F A A A A E A A E A, E E E L L L L L L L L L S L S L See Cd, ref. 44 F Air/C,H, None Graphite furnace See Ni, ref. 308 F Air/C,H, - (For Cu, see ref. 588) F Air/C,H, - Heated W wire Graphite furnace See Cd, ref. 1040 Ag tube insert in burner produces F O,/H,/N, CH-sensitized Ag emission Form complex of etharnbutol with F - Cu, in presence of NaOH, and extract with CH,.C0.C,H5 Dissolve in H,O, acidify with HCI and dilute to give a Co concentration of 15-20 ng/ml Graphite furnace (HGA-2100) Mix sample (19 parts) with carrier A 1 5 A d.c.(1 part) consisting of Cu fluoride/oxide containing 500 pg/g Ga as internal standard (Elements: Be, Cd, Co, Cr, Mn, Sb and Sn) Review (25 refs.) of separation methods F - for pg/ml or ng/ml levels of impurity elements, prior t o analysis by various methods including FAAS, AES, FES Mix with G30, i n a Pt dish, treat with HNO, and evaporate to dryness. Add acetic anhydride, warm gently, add methanol and heat to remove boron.Repeat with second portion of methanol, evaporate to dryness, add HNO, and re-evaporate t o dryness.Add H,SO, and ignite to 900 "C. Prepare standards in G%O, matrix A 1 2 A d.c. Hydrolyse and extract impurities at A D.c. arc pH 5.8 using NaDDC and 8-hydroxy qui noline, with CHCI, + isoamyl alcohol as solvent 69 2 308 -i + 588 990 2 =: 1040 $ 180 b 406 536 37 39 48 70Table 4.1 B CHEMICALS AND MISCELLANEOUS MATERIALS-coittiizucd Element X/nm Matrix Concentration Tech* form Sampie treatment Atomization Ref.Various - Various - (11) Various - Various - (5) Various - ( 6 ) Various - Various - Various - Various I Various - Industrial brines Trace levels Radioactive materials Trace levels Organic - micro-samples Polymers Trace levels Aqueous solutions Trace levels Titanium tetrachloride Trace levels Titanium tetrachloride Trace levels (AI, Cr, Ca, Mn, Fe, Sb) Pharmaceuticals - Pulp and paper products Trace levels Semi-conductor Trace levels materials Cellulose and paper - products Sugars - A E E E A A E E, A A A A A L L G S G L L L.s L L L L (A) Cold-vapour methods (Hg) (B) Hydride evolution (As) (C) APDC/MIBK extraction at pH 3 (Co, Cr, Cu, Fe, Mo, Ni, Pb, Zn) (D) Direct an,alysis, after dilution Combined GC/OES system for determination of C, H, N, 0, S, P, CI, Br, I, F and D Method for analysis of particulate contaminants Acidify with HCI or H,SO,, flush reaction vessel with argon and add NaBH, solution (30 g/I for Bi, Hg, Sb, Sn and 60 g/l for Pb, Te) To 10 ml TiCI, add 50 ml 7M HCI + 1 ml 10% KMnO,.Extract with 5 ml 0.2M trioctylamine in toluene (V, Fe, Mo).Add 0.5 ml 1M NH,I and extract with 5 ml trialkylbenzylammonium chloride in toluene (Cu, Zn) Remove TiCI, by vacuum distillation. Dissolve residue in HCI and introduce solution into graphite hollow-cathode Review paper on applications of OES and FAAS (12 refs.) Review (9 refs.) Dissolve (Gap, GasAs, InAs, e:c.) in 1:l HCI/HNO, and dilute Review of applicatioQs of AAS Mix sugar solution with acetate buffer + Rochel!e salt and extract with NaDDC/MIBK, to determine various elements, including Cu, Cr, Cd, Pb F - Graphite furnace Cold vapour Heated cell P ICP P Microwave (Ha) plasma Laser microprobe (Zeiss LMA 10) Heated SiO, cell (700-900 "C) F Air/C,H, Hollow-cathode (argon-filled, 500 mA) A , F - F - Graphite furnace P - F - 94 112 173 174 190 267 272 297 2 s- 331 2 8 433 ~ 423 ,b 429 5. 461 ?; 5 L? 2 5 .AVarious - Various - Various - (7) Various - (6) Various - (nonmetals) Various - Various - Various - Various - (5) Various - (7) (nonmetals) Various - Various - Various - Battery components - Thin films Paper - pg/g levels Silicon tetrachloride ng/g levels Solution residues Trace levels Miscellaneous Trace levels materials Pharmaceutical materials - Toys Trace levels Paint flakes Trace levels Semi-conductor films Major levels and/or major levels Organic compounds - Synthetic textiles Trace levels Semi-conductor films - High-purity Ba and Trace levels Sr compounds Graphite - A E A A A E A, E E E E E A A.E A E L S S L S s, L s, L S S S G L L L S Revsew of methods, including AAS, for F - the analysis of cathodes (Ca, Cr, Li, K, Si), anodes (Ca, Fe) and other components Review of methods (71 refs.) s - Laser beam Study of the characterization of papers Graphite furnace by trace metal content for the ciements Cu, Mg, Sb, Cd, Cr, Co, Pb, Mn, Fe.Digest with HNO, Evaporate at low temperature and dissolve residue in high-puri!y HF (Fe, Ni, Cr, Co, Cu, Mn, Zn) (CRA-63) Ag 9 Graphite furnace (CRA-63) Applications of direct analysis by hollow-cathode emission source Review (70 refs.) Screening test for toxic elemen!s in toys and playthings Semi-quantitative buffer method, on 0.1 mg sample Vacuum-deposit on graphite electrode. Method for analysis of binary films e .g . , Ni, Cr in Ni/Cr; P, Si in P/SiO, and Si, Al, i n Si/Al Introduce to plasma as thermally- generated vapour of organic compound.Results given for B, C, H, I, P, S, Si Review Investigation of FAAS, OES and MS methods Dissolve in HNO, and evaporate to low bulk, to pre-concentrate trace elements. Use pulse-nebulization technique on small aliquots of liquor None Cathodic sputtering Hollow-cathode - - A - A D.c. arc A 15A d.c. P ICP (500 W) F - A, F - F - S Laser + auxiliary spark 483 585 634 635 640 653 71 0 760 763 782 784 823 827 1039 1055Tab12 4.1 B CHEMICALS AND MISCELLANEOUS MAI"ERIkLS--conciltued 8 Element X/nm Matrix Concentration Tech.Analyte form Sample treatment Atomization Ref. Various Various Various (5) Various (9) Various Various Various (10) Various Various Various Various Various Various Various Various High-purity materials Multi-vitamin tablets Gallium arsenide Alcohol, acetone Drugs Drugs Miscellaneous materials Miscellaneous materials Anode slime Miscellaneous materials Acids, chemicals Metal complexes Toothpastes Helium Non-metallic borides I Trace levels Trace levels Trace levels - - - - - Minor and trace levels Trace levels - - - - A, F A E, A E A, E A E A E, A E A, F E E, A E A L L s, L L. s - - L L L, s L s, L L L G L Review Methods for Mn, Co, Cu, Fe, Mo F, P - 1106 Graphite furnace 1131 Comparison of OES and ETA-AAS methods, with 3 different sample treatments (A) Evaporate on impregnated graphite (B) Evaporate with graphite powder Review (70 refs.) Review (22 refs.) Multi-element determination of Mn, K, Rb, Ca, Cr, In, Sr, Ba, Na, Li using scanning Fabry-Perot instrumentation App I icat i ons of 2-c hanne I flame-AAS Comparison of FAAS and OES methods Review of furnace emission technique electrode and hom ogen ize Review of hydride-evolution technique Combined HPLC/OES system 100 mg sample 4- 10 ml 1N HNO, and dilute to 100 ml with H,O. Determine Na, K, l i by FES and o:her elements by FAAS Separate by GC. Elements: 0 (844.6 nm), H (656.3 nm), C (CH 431.4 nm), N (N, 391.4 nm) Comparison of 4 treatments. Elements: B (249.7 nm), Si (251.6 nm), As (193.7 nm) A 10 A d.c. 1147 Graphite furnace A D.c. arc 1189 - - 1221 - - 1223 F - 1243 1317 F - 1256 A, F - 1319 Graphite furnace 1340 (HGA-72) (HGA-2200) Heated SiO, cell 1342 F Air/Ar/H, P D.c. arc 1400 - plasma 2. (argon) F - 1462 f?, L. s 3 5 E. P 4 MHz 1468 '' k b ( Si 0, tube) 2 .; F - 1472 2 8 5

ISSN:0306-1353    

DOI:10.1039/AA9780800077

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

Chapter 4: Applications 91 4.2 METALS 4.2.1 Iron and Steels 4.2.1.1 Emission Methods. The application of an inductively coupled plasma to the analysis of steel has been studied (920). Accurate results were obtained for a wide range of com- positions and excellent precisions were maintained over periods of several days. Short term instability was occasionally observed however and this was attributed to fluoride in the test solutions which attacked the nebulizer.The ICP has also been applied to the determina- tion of Ce, La, Nd and Pr in plain carbon and low-alloy steels (20). Precisions of 4-6% were obtained. Akiyoshu and Tsukamoto (544) determined B in stainless and other steels at concentrations of 0.2-1 501 ppm by CMP, after first separating the B by distillation.Spark excitation with a constant-feed electrode was used to determine Al, Cr, Mo, Si and V at concentrations of O.OOl-O.Ol% in steel solutions (1187). Good reproducibility and rapid analysis were claimed. Perman et al. (1 184) reported that high-energy pre-sparking and an increased spark repetition rate gave, in a very short time, a micro-homogenized surface in the discharge region which considerably reduced inter-element effects.An Ar supported aerosol, sprayed into a stabilized arc, has been used for the deter- mination of P in iron (1 172). A combined discharge has been used for the simultaneous determination of C, Cry Mn, Ni and Si in steel (612), with detection limits of around 0.04%. Ottaway et al. (1244) have determined minor elements in steel by carbon furnace AES. Cr, Cu, Mn, Ni and soluble A1 were measured and a single set of atomization conditions was found to be optimum for all elements.Interferences from HNO, and Fe were small and correction for them was easily made. Butterworth (918) has examined the analysis of high-alloy steel using a glow discharge lamp. Operating conditions could be selected which resulted in common calibration curves for elements in high-alloy steels, high-speed steels, low-alloy steels, and cast irons.The determination of C in cast iron, using a GDL, has been investigated (43); care with the casting procedure was necessary for correct results to be obtained. Berneron (1063) has reviewed the application of the Grimm GDL to the analysis of metallic surfaces. The technique is useful for analysing films of various thickness (in nm-pm range) for most elements important in steel making.A frame cherniluminescence method (770) has been used for measurement of S in steels and cast iron at the 0.024.1% level. Hydrogen sulphide was formed in a hydride genera- tion cell and S , band emission measured with a filter photometer. 4.2.1.2 Absorption Methods.Antimony has been determined in steel after dissolution, using electrothermal atomization (362); concentrations from 0.00 141.03% could be determined accurately without the use of background correction. Papers continue to appear (274, 842) reporting the determination of Pb in steels using ETA, and all note that few problems should occur, although separation of high concentrations of Cr is recommended if the level of Pb is below Sppm.Andrews et al. (711) determined Pb directly by introduction of 1-12 mg solid samples of iron and steel into an inductively heated furnace. A detection limit of 0.05 pg g-1 and a RSD of GO.1 at levels greater than 1 pg g-1 was reported, with excellent agreement with certified results for CRMs. The discrete-sample nebulization technique has been applied to the determination of Bi, Pb, Sb and Sn in iron after extraction with tri-n-octylphosphine in MIBK (1032); 50pl portions of solution were injected into a micropipette tip attached to the capillary tubing.92 Analytical Atomic Spectroscopy 4.2.2 Non-Ferrous Metals 4.2.2.1 Emission Methods.A number of papers have described the application of the glow discharge lump to the analysis of non-ferrous materials. Copper-based alloys (242), silver (572) and aluminium alloys (889) have all been analysed successfully.Gough and Sullivan (628, 687) have described the application of a ‘boosted’ GDL (see Section 1.1-2) to the analysis of aluminium alloys, brass, zinc alloys and steel. The authors particularly recom- mended this system for the determination of concentration gradients and the study of surface layers.A similar system (691) has been used for the analysis of other alloys. Ten elements could be determined in 4-5 min. An inductively coupled plasma has been used to determine impurities in calcium (1 186). All of the elements sought were determined without interference from the matrix. Chlorine and 0 were determined indirectly: for C1, the differential determination of Ag after precipitation as AgCl was used and for 0, Ca was determined in the residue after vacuum distillation of metallic Ca and its nitrides.The applications of the ICP in metal analysis have been reviewed (161, 1084). Applications of the laser microprobe have been described (924, including the deter- mination of elements in gold, alumina and copper, and also the rapid discrimination of samples of Bi / In alloy from Sn / In alloy. 4.2.2.2 Absorption Methods. Peterson (695) has reviewed the applications of AAS to the analysis of non-ferrous alloys. Bowater et al. (129) have described the analysis of metallurgical samples by direct introduction of solids into a conventional resistance-heated graphite-tube furnace.Samples were supported in specially designed graphite cups. Aluminium alloys and bronzes were analysed successfully, but it was found that CRMs of similar composition were necessary for calibration. Rhodium, in automotive catalyst materials, has been determined using electrothermal atomization (963). Although the concentrations are low, the sensitivity of the technique allowed a simple acid dissolution to be used and the resulting solution to be injected into the furnace without further preparation.Selenium at the ppb level has been determined in a range of alloys by separation as SeO, followed by collection in a liquid N, trap and then analysis by ETA (1288). Detection limits as low as 0.05ppm in the solid sample were achieved. Graphite tubes impregnated with Mo, Si, Ta, Ti, V, W or Zr salt solutions have yielded improvements in sensitivity and tube life, and a reduction of interference effects in the determination of Sn in copper and aluminium alloys (727).Little degradation in tube performance was noted, even after 150 determinations. Copper in brass has been determined using a GDL specially constructed for AAS (1370).Solvent extraction has been used for the determination of Cd in tin (5%). Extraction by thiothenoylfluoroacetone into xylene was found to be quantitative. Bismuth has been determined in aluminium alloys with a molybdenum tube atomizer (226). Solvent extraction was necessary to avoid serious interferences.Table 4.2 METALS 0 s Element A/nm Matrix Concentration Tech.Sample treatment Atomization Ref. % form c1 Ag - Gold Ag - Silver Ag 328.1 Non-ferrous materials Ag - N i and Co alloys A!J - High-purity Pb, In, Co, Ni and Zn Al - Hig h-purity bismuth Al As As As As 0.02-0.2 Yo 9 5-99 O/O - F E A ng/g levels A 0.02-0.5 pg/g A Trace levels E 309.3 Ferro-van ad i uin Minor and 394.4 trace levels - Molybdenum, tungsten 50-500 p g / g - Steel - 234.9 Copper - - Iron, steel From 2 pug/g A S S L L L S L L, s L S L - - Add NH,NO, to avoid loss of AgCl i n heating stage Dissolve i n HNO,, mask wiih EDTA, adjust t o pH 7 with NH,OH and complex Ag, Bi, Cu, TI with NaDDC.Adsorb complexes on activated C, evaporate with HNO, at 150 "C, treat residue with HNO, and centrifuge Dissolve in HNO,, evaporate to low bulk, add tiron + NH,F, adjust to pH 9 with NH,DH and pass through PTFE column packed with AV-17 x 8 resin.Wash with H,O to remove Bi and mix resin + impurities (Al, B, Fe, Si) with BaF, spectroscopic buffer Treat 0.5 g sample with HNO, ( 1 : l ) ; fuse any undissolved material wilh K,COJNa,CO,, dissolve melt in HNO, and combine with original solution. Add HCI ( l : l ) , CaCI, + EDTA and dilute to 100 ml Method incorporates use of Na,WO,-impregnated graphite tubes Dissolve, with addition of HF to prevent interference by Nb, W, Ti, Si.Maintain excess of HNO, i n solution. Globule-arc method. Prepare standards by addition of oxides or nitrates to pure copper Indirect method, via foimation of molybdoarsenic acid in HNO, solution, followed by extraction into organic phase - Glow discharge Glow discharge Graphite furnace Graphite furnace (HGA-72) F - A 14 A d.c.Graphite fur iizce F - Graphite furnace A 6 A d.c. ( i n 0,) F N,0/CLH2 523 Q 527 b 1023 1121 g. 1229 2 665 994 33 34 265 34 1 v) wTable 4.2 METALS-contiizued x Element X/nm Matrix Concentration Ana'y'e Sample treatment Atomization Ref. form Au 242.8 Ag alloys 3-300 N / a A B - High-purity metals B 518 Aluminium and (Nb, W, Mo, Ta) (band) alloys B 249.8 Steel B B Bi Bi Bi 81 - High-purity bismuth - Steels - Malleable cast irons 223.1 Al metal Trace levels 0.001 -5 '/o E E E - Ni- and Co-base alloys From 0.1 hg/g A 223.1 Iron From 5 f i u / g A L L L L S - S L L L Dissolve in.HNO,, evaporate to dryness, Graphite furnace 271 heat at 260-280 'C, extract with H,O to obtain Pd and Rh salt solution, filter and fuse residue with Na,O, to obtain Pt and Au solution ( i n aqua regia).Ash at 350 "C (Au) or 1360 OC (others). Atomize at 2650 "C Dissolve in HF and distil BF, Dissolve in 6M HCI, with addition of HNO, as necessary, dilute and extract with 2-ethylhexane-1, 3-diol into CHCI, Dissolve in acid and fume with H,SO,/H,PO,. Cool, add methanol and distil to form methyl borate distillate for analysis See Al, ref 665 - Improved-performance method resulting from intensity/time study of sample excitation Dissolve i n 6M HCI, evaporate to dryness, redissolve in HCI and dilute to 1% Al solution.Take 1-5 ml aliquot, add 1 ml 3% EDTA + 2.5 ml 50% citric acid, adjust to pH 11-12 and extract with NaDDC into CCI,. Evaporate, redissolve i n HCI and add thiourea (5%) t o final solution Match standards to sample matrix Extract with TOPO/MIBK, t o concentrate Bi, Pb, Sb, Sn.Aspirate 50 pl aliquots by pulse-nebulization method (HGA-72) P ICP 35 F N,O/H, 36 P Microwave 544 plasma A 14 A d.c. 665 995 s - 86 - - b x Z' E b Mo microtube 226 3 furnace 5 Graphite furnace 599 2 F Air/C,H, 1032 5Bi - High-purity Pb, In, A L C 165.7 Cast iron - E S Co, Ni and Zn 0.02-0.5 &g/g Ca - Ti metal - A L Ca Cd Ce Ce - Steel 228.8 Tin 353.9 Steels 320.2 - Steels Trace levels 4-95 fiFI/Q Trace levels A L A L E L E S c o 240.7 Steels 12% level A S Cr 302.2 Vanadium alloys Up to 500 p s / g E L Cr 279.2 High-alloy steels 9-23 E S See Ag, ref. 1229 F - 1229 B Use Fe 271.4 nm as internal standard Grimm lamp 43 3 (1200 V; 150 mA) ?? (A) Dissolve and add Sr (10 mg/ml) F + K (1 mg/ml) as buffers (B) Separate Ca, Mg from Ti solution by ion-exchange and elute with 3M HCI Dissolve in HCI/HNO, and extract Fe from HCI solution with MIBK.Add 0.9% LaCI, to aqueous solution to overcome interferences by Fe, Si, P on Ca, Mg, Sr Dissolve in HNO, (l:l), evaporate to low bulk, dissolve in H,O and filter.Adjust to pH 5 with buffer solution, add o-phenanthroline soiution and extract Cd with thiothenoyl trifluoroacetone (STTA) into C,H, Dissolve in HCI/HNO,, evaporate to low bulk, transfer to separating funnel with 90% HCI and extract Fe with butyl acetate. Add final concentration of 500 pg/ml Fe, as internal standard Dissolve in HCI/HNO,. evaporate to dryness, redissolve in HCI and remove Fe by extraction with tributyl phosphate.Filter aqueous phase and add carbon powder f NaCI (lo//.) + Sc (60 pg/g ) . Evaporate and transfer to electrode F F P A Air/C,H, 273 b N ,O/C,H, s” -. Air/C,H, 1239 1320 Air/C,H, 546 I CP 20 A.c. arc 708 - Cathodic 1370 Introduce sample to plasma-jet in P 18 A d.c. 265 form of dry aerosol. Add Co internal argon plasma standard sputtering See also “Various,” ref. 477 s - 477\D Table 4.2 METALS-corztiizued a Element X/nm Matrix concentration Tech.Analyte Sample treatment Atomization Ref. form Cr Cr Cr cu c u cu c u c u c u c u c u Fe Fe Fe Fe 357.9 - 357.9 324.7 324.7 324.7 - - - 324.7 324.7 297.3 304.7 - 248.3 248.3 Steel Steel Li/B alloy Sheet metals Au/Cu and Ag/Cu alloys High-purity iron Steel, gold, aluminium Sieel High-purity Pb, In, Co, Ni and Zn Brass Ta metal Copper-nickel alloys High-purity bismuth Li/B alloy AI, Cu alloys - A 0.04-4.5% A A E E 0.1-100 pg/g A Minor levels F 0.002 -0.2 Yo A 0.02-0.5 pg/g A Major levels A 0.15 Hg/g level E E Trace levels E - A Trace levels A L L L L L L S L L S L L S L L Study of optimum conditions for Cr.F Air/C2H, Add NH,CI or 8-hydroxyquinoline N20/C2H, t o prevent interference by Ni Add buffer mixture of NH,CI f F N,O/C,H, MgCI, + LaCI, to sample solution to overcome Fe matrix effects D isso Ive in.H,O/H C 10,/H,02 F Air/qH, Asp'rate cons'ant flow of 0.5N HSI F H2/N2 into flame and introduce sheet metal sample through slit in burner assembly. Measure Cu emission from volatilized CuCl Dissolve in HNO, (Ag/Cu alloys) or P ICP HCI/HNO, (Au/Cu alloys) Dissolve (1 g) sample i n H,SO,/H,PO,/ F - H,O (15:15:70) and extract with HMA-HMDC into butyl acetate See Cr, ref. 670 See Ag, ref. 1229 Glow discharge F NIO/C,H2 F - Cathodic sp ut:er i ng - P Microwave plasma Prepare as acid solution. Use Cu A 6 A 296.1 nm, Ni 308.1 nm and Ni 300.4 nm as internal standard lines See Al, ref. 665 A 14 A d.c.See Cr, ref. 961 F Air/C,H, Extract Fe from solution as Fe(ll1)- F Air/C,H, thiocyanate complex with zephiramine, using butyl acetate solvent 505 670 961 181 252 31 7 523 670 1229 b 1370 3 1374 $ E 194 b si' $ 665 - 961 % 1240 5 2 8 h248.3 Cu alloys 313.5 Steeis - Lead - Nickel products - Tungsten metal 333.7 Steels 330.3 - Steels - Ti metal - Steel 285.2 Cast iron - Cast 'iron - Steel - Steel - Steel 279.5 Li/B alloy 386.4 Iron.steel Up to 100 pg/ml A (in soiution) Trace levels E pg/g levels A - A - E 0.01 -0.5 YO E Trace levels E A - 0.02-0.1% - F A 0.1-5 pg/ml A (in solution) Trace levels A - E 0.2-1 2% A A 0.014-0.31 96 E - L S - L L L S L S L L L S L L L Na - Non-ferrous metals - E, A L Nb 316.3 S:eels Trace levels E S Nb 408.0 Vanadium alloys Up to 500 p g / g E L Dissolve in HCI/HN3,, diigte and filter F Air/H, Dissolve and absorb Hf, Nb, Ta, Zr on A 18 A a.c.pyrogallol-formaldehyde resin. Ash, mix with C powder and pack in?o graphite elecirode Comparison of NAA, AAS and sp ec'rop hot ometric met hods Extract Ir, Ru from solution with 0.1M octylaniline chloride in toluene Dissolve in 15% H,O,, add Al(NO,), F - and dilute See Ce, ref. 20 P ICP - - Graphite furnace A A.c. arc See Ce, ref. 708 See Ca, ref. 273 F Air/C,H, N,O/C,H, Glow discharge - Dissolve in HCI/HND,, evapora?e to F -- dryness, dissolve i n HCI, dilute and li:,ur. Add Sr as ionization suppressor Add Sr (2000 pg/ml) to overcome F Air/C,H, interference by Al, Si See Ca, ref. 1239 F Air/C,H, See Bi, ref. 86 s - See Cr, ref. 670 F N,O/C<H, See Cr, ref. 961 F Air/C,H, Dissolve i n HCI/HNO,, evaporate almost P to dryness and redissolve in 2.5M HCI Comparison of FES and FAAS methods, F - in various soluiion media See Hf, ref. 253 A 18 A a.c. See Cr, ref. 265 P 18 A d.c. (in argon) I ?.%> MIP 1255 2 % 2 253 :? b 858 9 -. 824 M 1230 20 7c8 273 523 587 1193 1239 86 670 961 1393 1322 253 265\o 00 Table 4.2 METALS-contirzued Element X/nm Matrix Concentration lecn* Sample treatment Atomization Ret.form Kd Nd Ni Ni Ni Ni Ni P P P P Pb Pb Pb Pb Pb 391.1 366.5 - 352.5 225.3 232.0 - 232.0 - I (Mo) 255.3 253.6 214.9 213.6 213.6 - - 283.3 283.3 283.3 Steel Steel Ni/Sn alloys H ig h-alloy steels Aluminium Steel Li/B alloy High-purity metals (Nb, W, Mo, Ta) Iron, steel Iron, copper alloys Steels Molybdenum, tungsten Steels Copper Steels High-purity iron 0.01 -0.4 O h E Trace levels E - E 5.5-16% E 0.04-0.30 /ig/g A 0.02 -16.0'/0 A A Trace levels E - 100 pg/g level A E - 0.01 -0.06 '/o A 50-500 , d g A E - E - 0.1-100 pg/g A L S L S L L L S L L L L, s S S L L See Ce, ref. 20 P See Ce, ref. 708 A Maich reference standards for Sn P content of alloy. See also Cu, Sn, ref. 252 See also Cr and "Various," ref. 477 S F adjust to pH 4 with acetate buffer and extract Ni with capriquot (trioctylmethylammonium chloride) into isopropyl acetate See Cr, ref. 670 F See Cr, ref. 961 F Precipitate as metal phosphate and A heat with C at >1200 "C. See also B, ref. 35 Form molybdophosphoric acid in HNO, medium and extract with isobutyl acetate (indirect method) and pass through arc discharge Add NH,CNS to sample solution, F Nebulize solution in.argon stream A I CP 20 A.c. arc 708 I CP 252 - 477 Air/C,H, 552 N,O/C,H, 670 Air/C,H, 961 35 - 366 - - 1172 Application of RF-EDL source Graphite furnace See As, ref. 33 Graphite furnace See Bi, ref. 86 s - See As, ref. 266 Dissolve in HNO, or HCI/HNO, A 6 A d.c. Graphite furnace ( i n 0,) (CRA-63) See Cu, ref. 317 F - 1343 ' b 86 3 5' 33 3 ?", 2 266 274 $ 317 2Pb Pb Pb Pb Pb Pd Pr Pt Rh Rh Ru S S Sb Sb Sb Sb Se - Ni- and Co-base alloys From 0.05 pg/g 283.3 - High-alloy steels Trace levels 261.4 Iron, steel 0.1-100 pg/g 283.3 Iron From 2 pg/g 283.3 Cu alloys Up to 200 pg/mi (in solution) 247.6 Ag alloys 0.003-0.3% 405.6 Steel 265.9 Silver alloys 0.003-0.14 Yo 0.003-0.3% 343.5 Silver alloys 3-300 p g / S - Pt-Rh catalyst - - Nickel products - 384 Iron, steel 0.02-0.1% - S:eels Up to 0.25%0 ( S , band) 217.6 Steel 0.001 -0.03 O h 231.1 Lead-tin alloys - 231.1 Iron - Steels; lead alloys - Steel A A A A A A E A A A A E E A A From 15 pg/g A A - A - L S L L L L L L L L L S G L L L L L See Bi, ref. 599 Direct method, on 1-12 mg sample Graphite furnace Induction-heated furnace Separate Cr as CrCI,O, F - Sae Bi, ref. 1032 F Air/C,H, See Fe, ref. 1255 F Air/H, See Au, ref. 271 Graphite furnace See Ce, ref. 20 P ICP See Au, ref. 271 Graphite furnace See Au, ref. 271 Graphite furnace Dissolve i n HCI/H,SO, Graphite furnace See Ir, ref. 824 Graphite furnace See Bi, ref. 86 s - Dissolve in conc. HCI i n reaction F Ar/H, cell and collect evolved H,S in NaOH trap. Transfer aliquot to hydride evolu?ion cell and add HCI Dissoive in HNO, or H,SO,.Take 0.5 g Graphite furnace sample to final volljme of 100 ml and analyse 5 pl aliquot Fuse i n Zr crucible with Na,CO,/K,CO, F Air/C,H, 4- Na20,. Dissolve melt in 5% tartaric acid and add HCI. Boil, cool and dilute to 250 ml (for 1 g sample). Prepare standards i n matrix of 1% NaCl + 2% tartaric acid + 25% HCI See Bi, ref. 1032 F Air/C,H, - Graphite furnace (HGA-72) (HGA-72) (HGA-72) See As, ref. 34 F - Graphite furnace 599 71 1 842 1032 1255 271 20 271 271 963 824 86 770 362 380 1032 1450 34E Table 4.2 METALS-coiztiiiiied Element X/nm Matrix Concentration Ana'y'e Sample treatment Atomization Ref. form Se SI Si Si Sn Sn Sn Sn Sn Sn Sn sr Ta TO Te Te - .- - 251.6 - 284.0 - 286.3 286.3 224.6 31 7.5 - 293.4 - 214.3 - ~~ High-purity Cu, Ag, Au, Pb and Bi ng/g levels Molybdenum, tungsten H ig h-puri ty bismu t h Li/B zlloy Steel Cd/Sn alioys Alloys Pt/Sn alloy Iron Cu alloys Steel Steel Steel Iron, steel Metals Steels 50-5G0 pg/g Trace levels - - - Trace levels 1.85% love1 From 15 ILg/g Up to 200 pg/ml (in solution) 0.008% level Trace levels Trace levels UP to 100 rs/g 0.01-100 pg/g A A E A A E A A A A F A E A A L L, s S L L L L L L L L L S L L A, E L, S Evaporate from fused metal at 1100 "C under stream of 0,, trap SeO, i n liquid-N, vessel and dissolve in HNO,, with addition of Ni(NO,), solution to prevent furnace loss of Se See As, ref. 33 See Al, ref. 665 See As, ref. 34 Match standards for Cd content of alloy. See also Cu, Ni, ref. 252 Study of effect, of metal- impregnation of furnace Decompose by evaporation with H,SO,/H,PO,, dissolve residue i n H,O, filter to remove metallic Pt and aspirate filtrate See Bi, ref. 1032 See Fe, ref. 1255 Graphite furnace 1288 Graphiie furnace 33 A 14 A d.c. 665 F N20/C2H2 961 F - 34 Graphite furnace P ICP 252 Graphite furnace 727 F Air/C,H, 814 F N,O/C,H, 1032 F Air/H, 1255 Dissolve in HCI/HNO,, add HCIO,, evaporate t o fumes and dilute See Ca, ref. 1239 See Hf, ref. 253 Dissolve in HCI, complex with KI and extract with TOPO/MIBK Dissolve i n HCI/HNO,, evaporate, redissolve i n HCI ( l : l ) , filter, add As and precipitate by addition of hypophosphoric acid. Dissolve precipitate i n HNO, for analysis. Take 20 pl sample; atomize at 2400 "C Review of methods F Air/H, 1402 F Air/C,H, 1238 A 18 A a.c. 253 E- '1, F - 91 2 Graphite furnace 270 3 6.(HGA-72) A, F - 1116 Graphite furnace 2Ti TI TI V 'SJ Y Zn Zr Zr Zr Various (13) Various Various Var'ious (25) (6) Various (13) Various 395.6 Vanadium alloys 238.5 Copper - High-purity metals I Steel 400.9 Vanadium alloys (Pb, In. Co, Ni, Zn) - Steel 213.9 Copper alloys 313.9 Steels 339.2 Vanadium alloys 343.8 Al alloys - High-purity molybdenum - H'igh-melting metals (Mo, W, Nb, Ta) - Uranium - Mischmetal - Aluminium - Metals, alloys UP to 500 &g/g E - E 0.02-0.5 hg/g A 0.04-0.6°/~ A UP to 500 cLg/g E Trace levels E 0.01-37% A Trace levels E UP to 500 rg/g E 0.005-0.3 yo E Trace levels E Trace levels A Trace levels A YO levels A pg/g levels E Minor and A trace levels L S L L L S L S L L S L, s L, s L S S See Cr, ref. 265 P 18 A d.c. 265 (in argon) 'IJ_ See As, ref. 266 A 6 A d.c. 266 $ See Ag, ref. 1229 See Cr, ref. 670 See Cr, ref. 265 See Ce, ref. 708 F - 1229 * b F N,O/C,HZ 670 P 18 A d.c. 265 s' E! 6' A A.c. arc 708 $ (in argon) Dissolve in 50% tiNO,. If high Si F Air/C,H, 1278 present, dissolve in HF/HNO,/H,SO, and evaporate, before dissolution in HNO, See Hf, ref. 253 A 18 A a.c. 253 See Cr, ref. 265 P 18 A d.c. 265 argon plasma - P ICP 554 Dissolve in HNOJHCI, evaporate t o A 10 A d.c. 13 dryness, ignite t o MOO, at 500-550 "C and mix (1:l) wfith GeO,. Ignite at 700-750 "C to volatilize MOO, and concentrate impurities on GeO, See also As, Pb, Si; ref. 33 Graphite furnace 33 Study of performance for both liquid Graphite furnace 64 and solid (0.1 mg) samples Add 3000 pg/ml K.to eliminaie F N,O/C,H, 72 interference by Ce matrix. Results given for La, Pr, Nd, Sm, Eu, Gd Apply high-energy prespark in argon S Low-voltage 116 to remelt sample surface before analysis spark in argon Study of sample-handling and Graphite furnace 129 calibration errors i n relation to analysis of solid samples. Various results given for Pb c 0c1 Table 4.2 METALS-con tin u ed 0 N Element h/nm Matrix Concentration Tech.Ana'yte Sample treatment Atomization Ref. form Various Various Various Various Various (6) (6) Various (6) Various Various Various (21 1 Various Various Various Various Various Metallurgical materials Iron. steel Metals, alloys Copper alloys Cd metal Nickel alloys Zinc alloys Metallurgical products Metallurgical products Non-ferrous metals Metals and alloys Metals Metals Copper alloys All levels All levels Major and minor levels Minor and trace levels (TI, Pb, Zn, Ni, Cu, Sn) Trace levels (UP to 10 /la/a) Trace levels Minor levels - All levels Detailed study of sample dissolution procedures, for alloys, ores, sinters, slags, dusts, etc.Review (7 refs.) of reference materials for the iron and steel industry Dissolve 0.25 g sample in 15 mi acid and dilute to 50 ml.(Detailed study of wide range of metallurgical analysis) Direct method, for Cu, Zn, Pb, Sn. Ni, Fe Dissolve in HCI/HNO,, evaporate to dryness at 120-150 "C and load salts into cratered graphite electrodes Dissolve in HF/HNO, + few drops HCI, or, in direct method, weigh 0.2- 0.3 mg sample. (Elements: Ag, Bi, Pb, Se, Te, TI) Review (14 refs.) of availability of certified reference materials Instrumentation review, including AAS and OES Method review, including AAS and Unified numbering system for metals and alloys (Book) Description of 7.515 kV high-frequency a.c.spark source (UGE-4) Details of BNF disc standards for the OES or XRF analysis of many Cu-base alloys ICP-OES - F - 130 - - 133 P ICP 161 Glow-discharge 242 source (RSV) A 8 A d.c. 251 Graphite furnace 4 (CRA-63) S (argon 351 atmosphere) 4 - 358 b 4 - 359 g z -. 2 4 - 371 0 - - 385 5 Laser microprobe 428 5' t?, s - d - 477 484-~ Various (20) Various (9) Various (14) Various (6) Various Various (5) Various Various (9) Various Various Various (6) Various (7) Various Various Various Various (12) Copper Copper High-purity steels and Ni-base alloys Silver Copper alloys Steel Metals, alloys Alloys Metals Non-ferrous alloys Magnesium alloy Iron, steel, Al alloys, Ni alloys Al alloys Iron, steel Steels Steels Trace levels Trace levels Trace levels Minor or trace levels - Minor/trace levels A l l levels All levels Trace levels Trace levels All levels (trace up to 30%) Up t o 2% u p t o 3oo/s E E A E E E E E E A E F E E E E S S L S S S S S S L S L S S S L See As, ref. 266 Globule-arc method A 6 A d.c. A 9 A d.c. (in 0,) - F - See also Ag, ref. 527. Method for Au, Cu, Bi, Pd, Pt, Pb Study of structural effects on analysis A, S - of brasses and bronzes Application of combined spark/a.c. arc A, S - discharge to simultaneous determination of C, Si, Cr, Mn, Ni Study of evaporation rates of metals - - in H, atmosphere Applications of "boosted" (secondary Glow discharge filament) glow-discharge source As ref. 628 (above) Glow discharge Glow discharge Review (27 refs.) F - Dissolve in H,SO, and evaporate t o A 12 A d.c. dryness. Use Mg as internal standard for determination of W,Ta, Nb, V, Cr, Mo Applications of 2-channel, non- F Air/C,H, dispersive atomic fluorescence system (Cd, Zn, Mg, Ni, Co, Fe, Mn) Study of sample preparation and Glow discharge excitation conditions (Grimm) lamp Study of operating conditions Glow discharge (Grimm) lamp s - Report on ARL 34000 system Report on ARL ICP system.P ICP Prepare sample as 0.2% solution in HCI/HNO,. Treat any insoluble residue with HF/H,SO, and/or fuse with KHSO, 266 $ 488 % + 489 527 3 609 't.1 fi -.ol 612 61 3 623 687 691 695 772 806 889 918 919 920 c- 0Table 4.2 METALS-continued c 0 Element X/nm Matrix Concentration Tech. form Sample treatment Atomization Ref. Various Various Various Various Various Various Various Various Various Various Various (noble metals) Various (noble metals) Various (20) (17) (6) (7) Various (noble metals) Various (6) Gold, copper, Sn/ln alloy Metals and alloys Steels Al alloys Steels; Ni and Ti alloys Metal solutions Steel surfaces Ferrous materials Metals Metallic deposits Noble metals and alloys Gold and silver alloys Magnetic alloys Alloys Low-alloy steels E S E L E S E S E S E L E S A, E, F s.L E L A L A L A L A L A, E L, S A L - Laser microprobe Review P ICP s - Investigation of spark sources s - Description of new V.U.V.spectrograph S - General survey analysis system P ICP I Glow discharge (Grimm) lamp Review F, A - Review P ICP Strip deposit with HNO,/H,O (2:l) or F N,O/qH, HNOJHCI ( 2 : l ) Review of methods, including AAS - - Various extraction methods given, F - for Ag, Au, Pd, Pt, Rh Graphite furnace Dissolve 3 g sample in HNO,, add F - 0.5 g KCI and dilute to 100 ml. Method covers Co, Fe, Cu, Ca, Mg. Mn. Ni, Al + 12 rare-earth elements Review (317 refs.) - - (A) Dissolve in HCI/H,O, (Cu, Ni, Cr F Air/C,H, and Mn) N,O/C,H, (B) Dissolve in HNO, ( 1 : l ) or H,SO, (1:20) (A1 and Si) 924 928 998 1048 1050 1060 1063 1082 1084 1096 1113 1114 5 z 1118 ;i. a CI. 5 1123 3 t, ;i' 1139 5 2 2 "JVarious 4 Various I Various - Various - Various - Various - (7) (5) Various - ( 5 ) Various - Various - Various - Various - Various I Various - Various - Ancient bronzes Metals; weldings Indium metal Steels Calcium meial Steel Steel Alloys Steel Stainless steels Steel Uranium Iron, steel Metallurgical materials All levels - From 1 !-ah u p to 1% - 0.001-0.1 % 0.005-0.5% All levels - - - Trace levels I - E E E E E E A F E E E E E E S S S S L L L S S S S , G L L L Globule arc method A - - A - Direct method A D.c. arc - s - Results given for Mg, Si, Al, Fe, Mn, Cu P and CI Constant-feed electrode system s - ICP Method for Mn, Ni, Cr, Cu, Al. 'Atomic Fluorirneter' ' system Discharge lamp Graphite furnsce Dissolve in HNO, and filter (HGA-72) Line-intensity study s - Internal standardization study s - Metal aerosol technique P ICP Separate U by extraction with P ICP tributyl phosphate - P ICP 1173 1178 1182 1184 1166 1187 1244 1345 1373 1382 1413 1430 1434 - P ICP 1436

ISSN:0306-1353    

DOI:10.1039/AA9780800091

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

106 Analytical Atomic Spectroscopy 4 3 REFRACTORY MATERIALS No fundamentally new technique has emerged in this field of analysis this year; however, it is of interest to review the progressive consolidation and establishment of techniques reported earlier. For example, in AAS, flame atomization is still the most widely used, although in applications where only small quantities of sample are available (3, 80, 833) ETA has considerable merit.It is particularly valuable for archaeological and forensic work. Atomization in graphite cups has been favoured by several authors (643, 7973. For the dissolution of silicate samples, a fluoborate / boric acid medium, reported earlier, has been more generally used (80, 90). By contrast, for alumina, a H,SO, dissolution is now favoured by some authors (804, 820), instead of the more usual decomposition in HC1. In emission spectrometry, the technique of adding halides to the sample to enhance emission intensity (486, 783) appears to be well established.Continuing concern for the pollution of the environment has promoted the development of methods capable of high sensitivity. The use of either inert or controlled atmospheres with a d.c.arc source, to enhance the sensitivity, continues to be reported (658, 997, 999). 4.3.1 Refractories and Cements Price and Whiteside (42) developed a pressure dissolution method for a wide range of siliceous materials in which the sample was heated first with a mixture containing HF and then with an excess of B(O€€), in a sealed vessel. This method has been used by Hilligoss and Burton (90) for the analysis of high-alumina sand by AAS.Application of the method to micro-samples of about 0.01 g was reported by Price (%I). The materials were analysed both by AAS and ETA and included firebrick, feldspar, silica brick, iron ore sinter and a basic slag. The extension of the method for use in forensic science, clinical analysis and in archaeological studies was also described.Bastius (502) determined silica in high-temperature cement, magnesite, blast furnace cement and clay, where the contents of S O , ranged from 0.468%. Acid-soluble samples were dissolved by treatment with a mixture of HF and HC1 at room temperature in open plastic containers; acid-insoluble material was fused with LiBO, prim to acid attack.Silicon was determined by FAAS. It was claimed that no losses occurred due to volatilization under the conditions cited. Two papers have appeared on the analysis of magnesites (501, 597). The first described the effect of pre-ignition on results obtained by emission spectrography. The authors con- cluded that pre-ignition favoured only the CaO determination. In the second paper (the first of a series on the application of AAS to basic refractories) a scheme of analysis was given in which the main constituents could be determined f r m a single weighed sample. 4.3.2 Metal Oxides Jerabek et aZ. (820) determined trace metals in electrocorundum and alumina by FAAS following decomposition with H,SO, in a PTFE pressure vessel. Satisfactory detection limits were obtained for Cay Cr, Cu, Fe and Mg, although Mn and Zn could be present below the detection level of the method.Kuznetswa et al. (804) dissolved samples of corundum in 50% H,SO, in closed ampoules of quartz or Pyrex glass; Na was then deter- mined by flame photometry. The blank for Pyrex glass was 0.01% Na, but for quartz no blank was observed. Analytical conditions for the determinations of Re in alumina-based catalysts by flame AAS were studied by Sychra and co-workers (275); the interfering effects of A1 and Pt were examined- Traces of rare-earth metals were determined in oxides of gadolinium, samarium and yttrium by emission spectrometry in an Ar/O atmosphere (997).The authors, Dttrich et al., achieved detection limits ranging from 2 to 70 pg g-1 depending on the matrix.In a similar!2 Table 4.3 REFRACTORIES AND METAL OXIDES, CERAMICS, SLAGS, CEMENTS Element X/nm Matrix Concentration Tech. Anaiyte Sample treatment Atomization Ref. form - B - Silicon carbide 1-100 fig/g E Ba - Piezoelectric ceramics YO levels A Be - Alumina ceramics 0.01-20% A Bi 223.1 Tungstic oxide From 0.6 pg/g A Ca Cd Cd cu 315.9 Magnesium oxide - Ceramic tableware - Uranium oxide - W and Mo oxides - 0.02-2 pg/g @g/g levels c u 324.7 Rare-earth oxides From 0.07 @g/g 4 Fe 248.3 Glass 0.13-0.75 pg/ml A (in extract) S L L L S L S L L L Mix 20 mg sample with 5 mg NaF and excite in He atmosphere Study of flame conditions and F Air/C,H, interference effects N,O/C,H, Dissolve in H,PO, at 300-350 "C.F N,0/C,H2 At low Be levels, add LiCl (5000 pg/ml) to enhance signal Dissolve in 80% tartaric acid, adjust F Air/C,H, to pH 8-9 with NaOH and extract with 0.1M hexahydroazepinium hexahydroazepine-I-carbodilhioate into butyl acetate Co as internal standard of Cd from ceramic vessels Direct atomization of 1 mg sample Graphite furnace Dissolve in NaOH, adjust to pH 7.0 wi.h F Air/C,H, HCI and adsorb Cu, Zn on Chromosorb Graphite furnace W-HP column.Wash with H,O and elute either (A) with K I + H,SO, + ascorbic acid (flame method) or ( 6 ) With MlBK (non-flame method). (Column separation based on dithizone/ o-dichlorobenzene stationary phase) Dissolve in HCI, evaporate to dryness, F Air/C,H, redissolve in 0.1M HCI, dilute with HCI to pH 1.7-2.3 and extract Cu and Fe with 8-quinolinol into isobutyl alcohol Dissolve in HF/HCI and dilute to F Air/C,H, 2 ml (for sample weight of 0.1-1.0 mg).Use pulse-nebulization technique A 10 A d.c. Study of calibration lines, with s - F - Study of factors affecting release ( C RA-63) 254 Q b k! 1198 ", S' 1249 $* a 01 360 469 481 76 1 797 195 1326 3 + 0H Table 4.3 REFRACTORIES AND METAL OXIDES, CERAMICS, SLAGS, CEMENTS-continued Element X/nm Matrix Concentratioti Tech.Ana'y*e Sample treatment Atomization Ref. form Fe Fe Fe Fe K La L l Mg Mg Mg Mn Na Nb Pb Pb 302.0 Magnesium oxide - - Glass fragments - 248.3 Glass fragments up to 0.1% 248.3 Rare-earth oxides From 0.05 pg/g 766.5 K-Sr-Nb oxide 3% level 441.8 Barium titanate 0.05-6 YO (Lao) - Uranium oxide 1-25 M / g 202.5 Glass 2.5-15 pg/ml - Glass fragments - 202.5 Glass fragments Up to 2.4% 279.5 Glass 0.02-0.1 &g/ml (in extract) - Corundum - (in extract) - Carbon or silica mairices - 283.3 Glass 2-130 &g/o - Glass and ceramics - E A A A E E A A A A A E E A A S L L L L L S L L L L L S See Ca, ref. 469 s - Dissolve in PTFE pressure vessel Graphite furnace Dissolve in 40% HF in PTFE pressure Graphite furnace vessel and dilute (1:4) with H,O.Atomize at 2400 "C (Fe) or 2050 OC (Mg) See Cu, ref. 1326 F Air/C,H, Dissolve i n ( NH,),SOJH2S04, cool, F Air/C,H, add EDTA and precipitate Nb with NH,OH. Aspirate supernatant liquid for K, Sr determinations Fuse with LiBO, in Pt at 950 "C. F N,O/C,H, Dissolve in HCI 2nd add 10 ml 1% K solution before dilution to volume (0.1 g sample to 100 ml volume). Apply backgrourid correction at 441.65 nm See Cd, ref. 797 Graphite furnace (CRA-63) See Fe, ref. 3 F Air/C,H, Graphite furnace Graphite furnace See Fe, ref. 833 See Fe, ref. 1203 See Fe, ref. 3 F Air/C,H, Heat with H,S04 (1:l) i n closed F - SiO, ampoule Study of effect of additives (PTFE, A - LiF, C,CI,) on Nb, Ta emission 469 481 833 1203 1326 605 177 797 3 833 $ 1203 3 3 k 804 b 503 5' 2 $ S, L Comparison of solution and solid F Air/C,H, 643 x 2 z sampling methods Graphite furnace (CRA-63) L Fuse with LiBO, F - 1102 2Re 346.1 Al,O,-base catalysts - Si 288.1 Magnesium oxide - Si - Ores, clays, cements 0.4-68% sr Ta Ti Zn Zn Various Various (8) Various (9) 460.7 K-Sr-Nb oxide 25% level - Carbon or silica matrices - - Piezoelectric ceramics levels - W and Mo oxides pg/g levels - Glass and ceram'ics - - Siliceous materials - - Sand - TiO, YO levels A L E S A L E L E S A L A L A L A L A L - Ceramics (archaeological - pottery) Minor and E S trace levels A L Dissolve i n HCI/HNO, See Ca, ref. 469 ( A ) Treat acid-soluble materiais (B) Fuse acid-insoluble materials with HF/HCI with LiBO,, dissolve melt in HCI and add HF See K, ref. 805 See Nb, ref. 503 See Ba, ref. 1198 See Cu. ref. 195 F N,O/C,H, 275 2 s - 469 a 481 5 F N,O/C,H, 502 ? L 5 2 7 F - 805 g- A - 5c3 F Air/C,H, 1198 h F Air/C,H, 195 Graphi?e furnace N,O/C,H, See Pb, ref. 1102 F Crush, sieve to 200-mesh size and F treat 0.2 g sample with 5 m l H,O 4 2 ml HCI/HNO, + 1 ml 40°/0 HF. Heat to 160 "C in pressure vessel, cool, add 10 ml 40% H,BO, and reheat to 160 "C. Cool, add 5 mi 0.1 O h CsCl or KCI solution and dilute to 100 mi.(Results given for cement, slag, pottery. fire-brick, etc.) Decompose by acid digestion under pressure and prepare solution in fluoroboric acid/boric acid matrix. (Elements: Al, Fe, Ca, Mg, Ba, Na, K and Si) Mo and Co as reference elements. Meihod applicable to both ru:ile and anatase pigmen!s Grind (25 mg) and treat with HCI/HNO,, F followed by HF, followed by HNOJHCIO,, evaporating to dryness between s?ages.Dilute to 25 rnl, with addition of La, and determine Cr, Mn, Ni, Ti. Further dilute x5 for Fe, Al and x20 for Ca, Mg, Na F Mix (1:5) with C powder, adding A - 1102 Air/C,H, 42 N,O/C,H, 80 Air/C,H, 90 N,O/C,H, 10 A a x . 268 - 295r-. Tablc 4.3 REFRACTORIES AND METAL OXIDES, CERAMICS, SLAGS, CEMENTS-continued c 0 Element X/nm Mairix Concentration Tech.Ana'yte Sarnpie treatment Atomization Ref. form Various (22) Various (5) Various (12) Various (30) Various Various (23) Various 17) Various (Rare- earths) Various (Rare- earths) Various Various (12) (9) Various Plutonium dioxide 5-100 Pg/g Mzgnesite, s:n?ered - magnesium oxide Silicate refractories - Hig h-purity glass Trace levels Non-conducting materials - Mixed U/Pu oxides Trace levels Alum in a, corund urn Trace levels Rare-earth oxides Trace levels Lanthanum oxide 2540 pg/g level (Ce, Nd.Pr, Tb) Tellurium oxide Trace levels Cement, clinker, slag Major and and raw materials minor levels Cements, slags, ores All levels E A E, A A, E E E A E E E A A S L L, s L, s S S L S S S L L Ignite at 900 "C and mix 50 mg sample with 25 mg AgCl carrier + 0.13 mg (NH,),PdCI, internal standard.Make total weight to 500 mg with U,O,. Match standards for PuO,, AgCl and U,O, level. (Carrier-distillation method) A D.c. arc - (Si, Al, Fe, Mn, Ca) F - Automated system, using colorimetry, A, F - FAAS and OES Combined an.alytical system, including F, A - MS, OES, FAAS, NAA, ICP-OES, ASV P and chemical methods Mix sample with phenol-formaldehyde A (15%) 4- carbon powder (85%) mixture, homogenize and hot-press to form electrode briquette Mix with SrF, (8%) + Ga,O, (5%) carrier A Dissolve in H,SO, in PTFE bomb F Mix with carbon powder ( 1 : i ) .Method covers determination of Eu, Sm, Gd. Y, in Y, Sm and Gd oxides - A A Mix (1:l) with carbon powder and add NaCl (1 :30) t o mixture Grind, mix with Li,CO, -I- B,O, ( 1 : l ) end fuse in Pt at 1000-1050 "C.Dissolve melt in 2N HCI and dilute to volume, with addition of 1% LaCI, Comparison of fusion and acid dissolution procedures A F P I CP - - - (in Ar/O,) - 25 A d.c. Air/C,H, N20/C,H, I CP 486 597 663 669 773 783 820 997 7 s 3 x 999 z- loot $ $ 1176 '' t, 1423Chapter 4: Applications 111 study with lanthanum oxide (W9), they used atmospheres of Ar/O/N and claimed lower detection limits than prevously reported.Thus, they were able to determine Ce (40 pg g-I), Nd (25pgg-1), Pr (25pgg-1) and Tb (42pgg-1) in 20mg samples of lanthanum oxide. Examples of the use of ‘carriers’ in emission spectrography are found in the work of KO (783), in which impurities were volatilized from a matrix of uranium-plutonium oxides with an optimal mixture of SrF, and Ga,O,.Page et al. (486), working with the same matrix, preferred to use AgCl as carrier. T’he same authors also published a method (797) for the determination of Cd and Li in uranium oxide by AAS in which the powder sample was atomized directly from a carbon cup furnace. Extremely low levels of Cu and Zn were determined in tungsten and molybdenum oxides by Lorber and Mueller (195).Samples were dissolved in NaOH solution, and the Cu and Zn concentrated by column chromatography using dithizone in o-dichlorobenzene as the stationary phase. After elution with KI in H,SO,, the elements were determined by FAAS. For higher sensitivity they were eluted with MIBK and determined by ETA in a graphite tube.The working ranges were 0.5-400 ng g-1 of Zn and 4-400 ng g-1 of Cu. 4.3.3 Glasses and Ceramics Various methods were studied by Williams and co-workers (669) for the trace analysis of high-purity glass. Determination of some 30 elements was accomplished by techniques including AAS and emission spectrometry, with and without a plasma source. Many of the impurities in optical glass were in the ngg-1 range; in other glasses they were present at the pg g-1 level.Howden and German (8133, 1203) determined Fe and Mg in small fragments of window glass by AAS, for forensic purposes. The samples were dissolved in pressure vessels and the solutions analysed by ETA. Wall (3) has also characterized small samples of 0.1-1.0 mg of sheet glass and container glass by their Fe, Mg and Mn contents. This author used FAAS for solutions prepared by ultrasonic digestion in HF/HC1 at room temperature; 200 pl portions of sample solution were aspirated from small conical cups and the associated transient absorbance signals recorded. An interesting use of atomizer cups was described in a paper by Seimer and Wei (643) who determined lead in rocks, glasses and fly ash by AAS.Finely ground samples of these materials were mixed with graphite and loaded directly into graphite atomizer cups. These were heated to a temperature high enough to volatilize the Pb, while leaving the bulk of the matrix behind, Excellent agreement with published values was claimed for a variety of standard materials with Pb contents in the range 2-1 15 pg 8-1. Calibration was made using simple aqueous Pb standards. Workers in the Research Laboratory for Archaeology, Oxford, have devised a scheme (295) for the analysis of ancient portery by AAS. The decomposition was conventional, but the scheme of dilutions /additions permitted the determination of 9 elements per sample in batches of 50 samples at a time. The problem of metal release from ceramic tableware is of international interest, and standard test procedures involving AAS are in use in many countries. In a paper on the determination olf Cd, Carrol er al. (761) revealed that the test is sensitive to the lighting conditions. They showed that results may be changed by an order of magnitude by varying the exposure of the tableware t o light during the test.

ISSN:0306-1353    

DOI:10.1039/AA9780800106

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

112 Analytical Atomic Spectroscopy 4.4 MINERALS 4.4.1 Introduction The present day need of the geochemist is for the rapid analysis of a large number of samples, both for major constituents and for trace elements. Hence, where possible, sample preparation is reduced to a minimum and methods are selected that are capable of multi- element analyses. It is not surprising, therefore, that ICP spectrometry has made a large impact during recent years; it would be difficult to match its characteristics of precision, limits of detection and reduced interelement effects by any other technique.This year the literature has been flooded with papers on ICPs and Fassel (575) has produced a review on the applications of both ICP and AES in this field. The performance of conventional arc spectrometry i s being extended to satisfy the need for analytical data. Hare1 (667) determined 52 elements in phosphate rocks by a d.c.arc cathode layer method, and Lamothe and Seely (649) described the use of a direct- reading spectrometer for the rapid determination of 43 elements in a wide variety of geological materials. Atomic absorption spectrometry continues to play an important role in mineralogical analysis and although some papers (596, 843, 11 17) have appeared detailing comprehensive schemes of analysis, most publications refer to the determination of specific elements or groups of elements.Frequently, by chemical concentration and the use of ETA, very high sensitivity can be achieved. Interest continues in the determination of the precious metals at very low levels (104, 932, 1015, 1149) and this has been achieved both by emission and absorption techniques. 4.4.2 Sample Preparation Sample solutions have been prepared by a variety of means. Most commonly an acid attack is used, a popular medium being a mixture of HF and HClO,. This has been used to dissolve chromium ore (583), silicate rocks (346, 596, 1253) and lateritized rocks containing transition elements (843).A more versatile approach, however, is to dissolve the powdered sample in a HF mixture in a pressure vessel. This technique is now widely used. A com- prehensive report on acid dissolution techniques (843) has been published by Australian workers. Where the sample does not yield to acid treatment, conventional fusion methods, particularly with LiBO,, are favoured.An ingenious method for the analysis of coal by AAS was devised by CYReilly and Hale (50) who prepared slurries of the whole coal in water with a wetting agent (Triton X-loo), and aspirated them into the flame. Aqueous calibration standards were used. Good results were claimed for Ca and Fe at the minor level and Pb and Zn at trace level. 4.4.3 Atom'ic Emission Spectrometry A high-power arc system was developed by Sukhnevich (611) in which powder samples were introduced into a 6000V horizontd arc by means of a special vibrating device.Results on silicates, dolomites, magnesites, and quartzites showed better reproducibility than by conventional arc sources. The system also permitted the determination of Br, C , C1, I, N, P, S and Se.Other Russian authors (261) employed a horizontal arc with powdered samples for the determination of Au. A scintillation mode of measurement was used in which light pulses due to individual grains of Au were recorded. A working range of 0.03-50 p g g-1 was claimed. Watson and Russell (675) determined trace elements in geological samples by direct- reading OES. Graphite and LiF were used as the buffer and germanium oxide as internal standard, Samples were excited in a double-flow gas stabilized jet discharge ofChapter 4.Applications 113 Ar/O,. The authors claimed a rapid analysis with the results for Co, Cr, Cu, Mn, Pb, V, Zn and Zr in agreement with published data on standard samples; the RSD was 0.1-0.15. Preconceiztrcrtion has been used by several authors prior to spectrographic analysis. For example, Kukarina and Kalmikova (1205) extracted lanthanides from aqueous solution with diantipyrenylmethane dissolved in CHCl,.Leinz and Grimes (972) concentrated W by extraction of the thiocyanate complex with ether and achieved a detection limit of 0.2 pg g-l. A fire-assay preconcentration was used by Harris et al.(1149) in the determination of Au and platinum metals at the 0.08 pg gl level. Of the many papers published on the use of inductively coupled plasma sources, those of most general interest include that of Watson and Russell (21), covering the analysis of a wide range of materials, and the combination of a selective extraction technique with ICP for multi-element analyses at the sub-microgram levels, reported by Motooka et al.(944). Rurman and co-workers (960) used LiBO, fusion to decompose rock samples prior to ICP spectrometry and overcame many of the practical problems associated with the use of this compound by reducing the amount af flux used and taking advantage of the ability of the ICP to breakdown thermally stable complexes, Date (41 5) devised a useful method for the preparation of trace element reference standards.A co-precipitation technique was used in which standard solutions were mixed with tetra-ethyl orthosilicate solution and then ammonia added to produce a gel. After the gel had been dried, the standard material was ignited and thcn ground in 3 Tuna mill. Golightly and Anne11 (93’3) have published a brief history of the use and development of AES techniques by the US.Geological Survey. 4.4.4 Atomic Absorption Spectrometry In AAS, as in emission spectrometry, many determinations have been made at extremely low levels by preconcentration of the analyte by solvent extraction. A ‘blanket’ reagent, Aliquat 336 (tricaprylmethylammonium chloride) in MTBK, has been proposed by Viets (942, 953).Trace metal halides were extracted by exchanging with the chloride ion of the reagent, or as oxonium ion pairs with the solvent. Metals quantitatively extracted were Ag, As, Bi, Cd, Cu, Ga, Hg, In, Pb, Pd, Pt, Sb, Sn, Te, T1 and Zn. Other extraction procedures include that published by Campbell and Simon (1148) for extracting Be with acetylacetone, and by De et al. (346) for separating Ga with cupferron in MIBK.Chao and co-workers (943) removed Te from solution in HBr by extraction with MIBK; they also described an ether extraction for the isolation of Co, Cu and Ni. In the analysis of uranium concen- trates, Naeem and Capdevila (826) removed the uranium matrix by extraction with tIibutyl phosphate in hexane before determining As, Ca, Fe, Mo and V by FAAS.Fryer and Kemch (203) separated traces of precious metals from solutioiis of rock samples by co-precipitation with Te(N) and SnCI,; the Te was removed by dry ashing. Silver, Au, Pd, and Pt were determined at pgg-1 levels. Sember and co-workers (104) concentrated Au by adsorption on activated carbon prior to analysis by flameless AAS. This technique was also used by Barakat et al.(14633 for concentrating Au from rock samples prior to spectrographic analysis. An ingenious combination of flux and buffer was described by Tomesanyi (723), who used a mixture of SrCO, and B(OH), to fuse bauxite and red mud. The application of the SrCO,, a good ionization buffer, overcame matrix effects in the analysis by AAS.er Table 4.4 MINERALS U -b Element A/nm Matrix Concentration Tech.Sample treatment Atomization Ref. form Ag - Rocks 0.2-100 ng/g A L Grind (<20 pm), digest with HCI/HNO, Graphite furnace 203 and evaporate to dryness. Repea! acid digestion, decant filtrate, centrifuge and re-digest any reslduo. Treat extract with HF, evaporate to dryness, dissolve in HCI with addition of Te(lV) solution -I- SnCI,, boil and filter. Dissoive residue in HCI/HNO, (HGA-2100) - Rocks, soils, sediments From 0.02 pg/g A L Grind to 80-mesh size and digest F Air/C,H, 953 1 g sample with 1 g KCIO, 3. 4 ml c o x . HCI. Add 8 ml 20% ascorbic acid solution + 10% KI solution and extract Ag, Bi, Cd, Cu, Pb, Zn with Aliquat-336 (tricapryl methyl- ammonium chloride) into MlBK Ag 328.1 Ores Ag - Ores 1 -10 ng/g A L Separate Pt group metals by F Combined 1515 cupellation graphite boat -quartz tube system 0.01-0.30 ccg/ml A L Dissolve i n HNO, or HCI/HNO,, add F Air/C,H, 1128 ( i n extract) excess of HCI and treat any residue with Air/propane HF/H,SO,, fol!owed by HCI/HNO, As - Geological materials Trace levels A G Detailed study of hydride-evolution Heated SiO, tube 402 method, for As, Sb and Te 3 As - Uranium concentrates 0.1-2% A L Remove bulk of U matrix by F Air/C,H, 826 $ extraction with tributyl phosphate in hexane a, Au 242.8 Cyanide leaching solutions From 0.02 mg/l on A L Dry at 200 "C, ash at 900 "C and Graphite furnace 104 5 ,uI sample atomize at 2400 "C Au - Rocks 0.2-100 ng/g A L See Ag.ref. 203 Graphite furnace 203 6. AU 267.6 Geological materials 0.03-50 hg/g E S Direct method, on powdered material A 13 A d.c. 261 % Au 242.8 Ores 1-10 ng/g A L See Ag, ref. 1015 F - 1015 8 (FLA-10) 3 (< 50 pm particles) 2 (HGA-2100) hBe 234.9 91 Ca Ca Cd c o Cr c s c s c s c s Standard rocks Rocks, soils, sediments Uranium concentrates Magnesite Rocks, soils, sediments Geological materials Geological materials Rocks Geological samples 852.1 Ores - Silicate rocks cu - c u - c u 324.8 c u - Geological materials Rocks, soils, sediments Ores Rocks 0.024-8.75 &g/g A L From 0.2 bg/g A L 0.15-3% A L From 0.02 bg/g A L Minor and trace levels A L I A L E L A L 5-1000 bg/g A L From 0.02 pg/g A L Up to 40% A L (chalcopyrite) - A L Disso!ve i n HF/HNO, in PTFE bomb.Adjust to pH 8, add EDTA and extract Graphite furnace (HGA-2100) Be with xylene, as acetylacetonate.Back-extract with 3M HCI See Ag, ref. 953 F See As, ref. 826. Add La solution for Ca determination, to overcome interference by Al, U Dissolve i n HCI. (Comparison with XRF and gravimetric methods) F F See Ag. ref. 953 F Interference study F Dlssolve in HF/HCI, evaporate to dryness, add HCIO,, evaporate and dissolve residue i n H, PO, See Li, ref. 374 F Mix sample with KCI-buffered A SiOJgraphite mixture.Prepare standards by dilution of standard mineral (lepidolite) containing 0.075% Cs, 1.82% Rb and 2.50% L i Digest with HF/H,SO,, evaporate to dryness, dilute with H,O/H,SO, and filter Decompose with HF/HCIO, by repeated evapora:ion, disso!ve in HCI/HNO, and add H,BO, + NH,NO, + Na molybdo- phosphate, to separate Cs, Rb by co-precipitation. Dissolve i n 0.5M NaOH for analysis See Co, ref. 943 F See Ag, ref. 953 F F F F Decompose by repeated evaporation with F HCI/HN03/H,S0, and adjust final soiu?ion to YO HCI strengih - F Air/C,H, Air/C,H, N20/C,H, Air/C,H, - d Air/C,H, - - Air/C,H, 4 Air/C,H, Air/C,H2 A ir/p rop a ne Air/C,H, 1148 2 +$ 3 953 ?? 2 b 826 1297 $ M 953 943 583 374 650 801 1253 943 953 1132 1257 c wF 529.1 Rocks 529.3 (CaF) Fe - Zircon beach sarrds 0.@5-0.5?0 Fa 386.0 Lateri?e Fe Ga - Uranium concentrates 0.15-3Y0 - Bauxite; silicate rocks 5-100 p g / g t A, E A A Ir 208.9 Ores K - Feldspar LI - Rocks Li - Geological materials 0.5-5 j g / g E Mg A - Rocks - Mg 285.2 Phosphorite: apaiite; 0.025-1 /ig/ml A Mn 279.5 Geological mater i a Is 1-20 bg/ml A H,PO, products ( i n extract) ( i n extract) S L L L L L L S S L L L S:udy of excitn:ion conditions.A Dn:zciion limit 0.005% F L I S ~ ai'h NaLOL iP!a,CO , extract v/i'h H,O, boil to precipitate Zr + Fe as hydroxides and dissolve in HCI. (Resuls of AAS and ICP-OES compared v;r;h XRF and s?ectrophoLorne:r.c resiliis) F P Grind, sieve (20-mesh), re-grind ard sieve (150-mesh). Digest 53 mg sample wi:h HZI/HNO,/HF, in PTFE vessel, add H.69, sqd dilyfe to \/olcmo (100 ml) F See As, ref. 826 F Decompose wi.h HF/HCIO,, rGmcve F mixed oxide group elements with NaOH, fiiter and extract Ga with cupferron/MIBK See Ag, ref 1015 F Comparison with M8 method F Mix (1:5) with buffer of BaCO, + F 19 A d.c. N,O/C;H, I CP Air/C,H, Air/C,H, - 4 - Air/C,H, BaCI, + SiO, ( 8 : l : l ) (screw-rod method) See Cs, ref. 650 A - Application of split-capillary device F - for independent introduction of bbffer and sample solutions F Air/C,H, - Treat with HF/HNO, i n PTFE vessel, F N,0/C2H, evaporate and dissolve in HCI 262 379 768 826 346 1015 1268 374 5 2 Y 650 & 809 ;a 0 815 r, h -. 1 -. 2. 2 2 z 1150 P '=:n Mo 313.3 Mo Ni NI Pb Pb Pb Pb Pb Pd Pd Pd Pt Pt Rb Rb Rb Rb Rh Rh - 232.1 - 283.3 - 283.3 - I - - 244.8 - 265.0 - - 794.2 - - 343.5 Cu/Mo ore flotation c once n t r a!es Uranium concenirates Coal, coke Geological materials Rocks Rocks, soils, sediments Ores Lunar samples Rocks Rocks Rocks Ores Rocks Ores Rocks Geological materials Ores Silicate rocks Rocks Ores % levels A 0.1-1 Jh A 1 iLg/g level A 5-1OCO @g/g A 2-115 Fg/S A From 0.2 pg/g A From 0.0246 A Trace levsls A - A 0.2-100 ng/g A From 0.1 ng/g A 1-10 ng/g From 0.8 ng/g 1-10 ng/g - 0.5-5 N/Q 47-74 PB/g 1-10 ng/g - From 0.1 ng/g L L L L S L L S L L L L L L S S L L L L Treat wiih HNO,, evaporate to low bulk, F N,O/C,H, sdd HCI, filter and dilu!e.Add Na,SO, + citric acid and make final solution am m or1 i ac a I See As, ref. 826 F N,O/C,H, Treat with HF/HNO,, evaporate to F Air/C,H, low bulk, add HNOJHCIC),, evaporate, dissolve in HNO,/HCIO, and di1u:e.Filter and fuss residue with Na,S,O, See Co, ref. 943 F - Grind, mix with graphite powder See Ag, ref. 953 F Air/C,H, See Cu, ref. 1132 F Air/C,H, Stlidy of thermal release profiies for PbCI, or other chemical forms of Pb Graphite furnace and a!omize directly in furnace ci?p (CRA-63) Air/propane Graphite furnace - F - See Ag, ref. 203 Graphite furnace Fuse ground sample (20 g) with PbO + Graphite furnace Na2C0, + borax glass + flour and cupel the resulting Pb button to form Au bead (2.5 mg) containing Pt me!als. Dissolve in HCI/HNO, (HGA-21 00) See Ag, ref. 1015 F - See Pd, ref. 932 Graphite furnace See Ag, ref. 1015 F - See Li, ref. 374 F Air/C,H, See Cs, ref. 650 A - See Cs, ref. 801 F - See Cs, ref. 1253 F Air/C,H, See Pd, ref. 932 Graphite furnace See Ag, ref. 1015 F - 553 s % 2 $ 539 "J 2 826 3 -. s 943 643 953 1132 1238 1257 203 932 1015 932 1015 374 650 801 1253 932 1015 -4Table 4.4 MINERALS-contirzued ~ - Element X/nm Matrix Concentration Tech. Analyte Sample treatment Atomization Ref. form Ru 349.9 Ores 1-10 ng/g A Sb - Geological materials Trace levels A Si 251.6 Fluoride-bearing minerals 0.1-3% A Te Te Ti Ti U V V W 214.3 Geological materials 0.1-20 pg/g (flame) 4-200 ng/g (flameless) - Geological materials Trace levels 365.4 Silicate rocks Minor and trace levels 363.9 Rocks 40 /J.g/Q-5% 378.3 Ores - 318.3 Rocks - A A A A E A - Uranium concentrates 0.1-1% A - Geological ma!erials From 0.2 pg/g E Zn 213.8 Coal, coke 1 pg/g level A Zn - Rocks, soils, sediments From 0.02 pg/g A L G L L G L L L L L L L L See Ag, ref. 1015 F - See As, ref. 402 Fuse with N%O, or digest with F N,0/C,H2 acid in PTFE bomb. Adjust final solution to contain 3000 mg/l Na (as NaCI) -t l-so/a HCI + 10-200 mg/l Si Treat with HBr/Br, solution, shake and F Air/C,H, heat at 135-140 "C for 30 min. Dilute Graphite furnace with H,O t o approx. 3M HBr strength, add ascorbic acid and extract with MlBK See As, ref. 402 Digest with HF/HCIO,, evaporate to low F N,O/C,H, bulk and redissolve in HCIO,. Add Na, Fe and Al to calibration standards Decompose sample by fusion or by F N,0/C,H2 HF treatment and adjust Al content of analysis solution with C,H,OH/H,O mixture Decompose silicates with HF/HCIO,. sulphides with HCI and carbonates with HCI + fusion of insoluble residue.Match standards for Ca. Al, Fe, Mg. Ash at 1700 "C and atomize at 2650 "C See As, ref. 826 F %0/C2H2 Fuse with KOH, extract with H,O. A D.c. arc acidify, reduce with Tic$, complex with CNS- ion and extract with ether. Evaporate aliquot of ether solution on to Na,CO, in electrode cavity Heated SiO, tube (CRA-63) Heated SiO, tube Digest with acid, filter and dilute P ICP Graphite furnace (HGA-72) See Ni, ref. 539 See Ag, ref. 953 F Air/C,H, F Air/C,H, 1015 402 227 231 402 243 1029 1429 276 b % ?- 3 2. a 826 972 $ s.n Zn 213.9 Various - Various - (5) Various I Various - (7) Ores Ores, sands, leaches, residues Minerals Coal Minerals (drill cores) Silicate rocks: bauxites Various - Minerals (rare- earths) Var'ious - Rocks (11) From 0.02% All levels Trace levels Minor (Fe.Ca) and trace (Na, Ni, Pb) levels Minor and trace levels Major levels Minor and trace levels Traca levels Vafious - Geochemical samples - A E E A E A E E A - L L S S/L (slurry) L L S L L - See Cu, ref. 1132 F Fuse with Na,O,, dissolve in HCI P and add Sc as internal standard. For samples no: requiring fusion, add NaCl + Sc. (8 analytical applications given) Blow powdered sample direc.ly A into arc discharge Grind, sieve to 80-mesh size and F prepare as slurry (0.01-1 O/O solids) in 0.1% Triton X-100 solution.Stir continuously during aspiration Digest with aqua regia P (A) Fuse with Na2C0, + Na,B,O, F (B) Digest with HF/HNO,/HCIO, Add Na, La as buffer elements and match standards with Al. Fe for Ti determination and with Al for Ca determination.Elements: Al, Si, Ti, Fe, Ca, Mg, Mn Mix ground sample (1 part) with buffer material (2 parts) cons'isting of graphite powder (60%) + synthetic granite matrix (30%) + N%CO, (10%) A P - Study of matrix interferences. Calibrate by (a) method of standard additions, or F (b) synthetic-matrix standards, matched t o major elements Methodology review, related to - exploration geochemistry Air/propane C,H, I CP - A i r/C, H I CP Air/C,H, N,O/C,H, 28 A a.c.I CP - - 1132 % 5, 21 r: ? b =: 32 2 50 2 2 .5 6- 158 258 263 286 348 353Table 4.4 MINERALS-continued I 8 Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. form Various Various (23) Vafious ( 6 ) Various Various (5) Various Various Various (8) Various Various (43) Various Various Various (52) Rocks and minerals Sediments Cr-bearing ores Geochemical materials Magnesite Geochemical samples Rocks and minerals Minerals Geological materials Geological ma:erials G eo! og i cat samples Silica?e minerals Phosphate rocks All levels E Trace levels A YO levels E Trace levels - Major/minor levels E - All levels E A Minor and trace levels E E Trace levels E ( + 10 major elements) Major levels E I E - E - L L L - S L L S S S L S S (A) For trace elements, dissolve i n HF/ P ICP 363 HNOJHCIO, and d'ilute with 5% HNO,.(B) For major elements, fuse with Na,O, and dissolve in HCI or, fuse with LiBO, and dissolve in HNO, - F - Fuse with NpO,, dissolve i n HNO, and P ICP dilute to volume, with addition of Sc as internal standard Description of trace element reference - - standards, prepared by co-precipitation with SO, Mix sample with COO internal standard A - and powdered C, in ratio 4:1:20 Review (41 refs.) P ICP Fuse with NaOH and complete F - dissolution with HF/HCIO, treatmen:.(Comprehensive scheme, including some spectrophotometric determinations) 364 392 41 5 501 370 596 Evaluation of DG-2 high-power arc, A "High-power" 611 5 n '4.N, C and P Study of exci?ation conditions A 1 5 A d c . 6 4 8 % €49 k Mulii-channel, computerized, direct- A - reading system. Add RbCl as 3 for determination of Se, CI, Br, S, I, arc (6000 V) - - -. I spectroscopic buffer z. Review P ICP 651 Photographic OES method for toxic A D.c. arc 658 5 Use Ca metaphospha:e + graphite as A - 667 2 0 k standard matrix elements, e.g., Sb, As, Cd, Hg, TI, Se -L 1 , >Various Various (7) Various Various Various (41 1 (9) Various Various Various Various Various Various (13) (18) Various (6) Various (12) Var'ious Var'ious (43) (9) Geological samples Bauxite: red mud Rocks, minerals Coal fly ash Laterites - Major levels - - - Geological materials Geological materials Geological materials Geological materials Geochemical survey samples Geological materials Geological materials Rocks Fly-ash particle fractions Rocks, ores All levels Trace levels - All levels - Trace levels Trace levels YO levels (7) and minor levels (5) A l l levels YO levels (major constituents) E A E A A E E E E E E, A E E A A S L L L L L, s S L S S L L L L L Mix with graphite/LiF mixture, A D.c.arc containing Ge as internal standard Fuse with SrCO,/H,BO, mixture a: F N,O/C,H, 1090 "C.Automated sys:em for the elements At, Fe, Si, Ti, Ca, Mg, Na Study of matrix effects due to flux P ICP materials (Na,B,O,, H,BO,) Inter-iaboratory comparison of FAAS F - and NAA analysis ( A ) HCIO, (B) HNOJHCIO, (C) HF/HCIO, (Elements: Cr, Co, Cu, Fe, Mn, Ni, V, Zn, Pb) A history of OES i n U.S.Geological A, S - Survey, Washington Laboratory Review of methods for improved limits A D.c. arc of detection Eackground correction system P ICP comparison of 3 treatments: F - - Mobile OES laboratory A D.c. arc (in Ar/O,) A - Review of applications of a selective P ICP extraction method, based on, Aliquat-336 F - and MlBK Graphite furnace Separate As, Bi, Pb, Sb. Sn, Mo from P ICP major constituents by selectivs organic extraction method crucible, at 1000 "C.Dissolve melt in HNO, and dilute Combined FAAS, XRF, NAA procedure F - Fuse (1:l) with LiBO, i n graphite P ICP Decompose wi:h HF + BF, in PTFE F N,O/C,H, pressure vessel. (Interference study) Air/C,H, Air/propane 675 723 732 812 843 933 934 935 936 94 1 942 944 960 1003 1117L- Table 4.4 MINERALS-continued t.4 LI p.> Element X/nm Matrix Concentration Tech.Analyte Sample treatment Atomization Ref. form Various Various (5) Var'i o us Vatious (noble metals) Various Various (rare earths) Various Various Various Various Various Bauxite - A Ores - E Geological materials I A Geological materials fig/g levels E Bauxite Loparite Ores, sands, matte-leach - residues A E E Sulphide ores Minor and trcce levels A, E Geological materials - Rocks - E A Geological samples - E L L L S L L, s L L, s S L L Fuse (1:10) with &S,O, and dissolve melt in 2N HCI.Treat any residue with 30% KOH solution, dissolive in 2N HCI and combine extracts Dissolve in HCI/HNO,/H,SO, (:!:2:1) A and add KCI buffer + 5% isoptopyi alcohol (Cu, Cia, In, Ni, Mn) Review F Concentrate by fire-assay, using Ag A as collector for Au, Pt, Pd and pt as collector for Pd, Rh, Ir Digest with HF in PTFE autoclave at 710 "C, add H,BO, and dilute Digest with HF in Pt crucible, add H,SO, 3- few drops HNO, and evaporate to low bulk. Redissolve in HCI/li20, add Er and evaporate to dryneso. Dissolve residue in H,O, adjust to pH 5, add KI 3- ascorbic acid and extract with diantipyrinylmeihane in C H ~ I , . Separate "third-phase" for OES F F A Applications review with methods P Review of methods, including FAAS, ICP-OES, NAA and XRF conditions) Critical comment and reply, relating to earlier paper on P, Si in rocks (Riddle and Turek; Anal. Chirn. ,kta, 1977, 92, 49) nebulizer function) - Mix with KCI (Study of buffer A F Fuse (1:l) with LiBO,. (Study ot P N,O/C,H, Air/C,H, Arc-in- spray system 12 A d.c. - 11 A d.c. I CP - 20 A a.c. - I CP 1135 1137 1138 1149 1194 1205 1206 > 3 *- c? 1220 ;. 0 T h 1300 1323 2. 1324 t/l $ x I? 8 1424 '5 cChaprer 4: Applications 123

ISSN:0306-1353    

DOI:10.1039/AA9780800112

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

124 Analytical Atomic Spectroscopy 4.5 AIR AND WATER ANALYSIS 4.5.1 Introduction There have been few significant advances in the field of environmental analysis over the past year, but rather there have been refinements of existing techniques and modest improvements in their reliability or range of application. On the instrumental side the trend towards the use of ETA in AAS, particularly for air analysis, has continued.The ICP is now clearly becoming a major source for rapid multi-element analysis by AES for water analysis. In fact, the tendency towards the use of this and other devices that result in a saving of manual labour would seem to be a portent of things to come. One development already well established is the use of microprocessors in AAS to reduce operator time and there are signs of increasing interest in the use of some form of automation in the sample preparation step.The precision and accuracy of new or existing analytical techniques are of great interest, especially at the low concentrations encountered in much environmental work. The precision of a particular method in a given laboratory is relatively easy to check, although many published reports still seem to lack adequate data in this respect.The accuracy of analytical data on a world wide basis is of growing concern, particularly in the environmental field where important economic, political or hygiene decisions may be based on the analyst's report. Probably the most convenient and reliable way for an individual laboratory to check the accuracy of its techniques is by analysis of certified reference materials (CRMs).Schroder et al. (937) have described the library of 65 standard water samples assembled by the US. Geological Survey over a period of 13 years (see 3.3). Olsen and Fassel (1819) have reported an air-filter calibration facility and the preparation of four sets of air particulate standard filters. An alternative to the use of CRMs is participation in inter-laboratory comparisons.Dybczynski er al. (533) have conducted a statistical survey of the results obtained by 35 laboratories in 19 countries for 16 trace elements in water samples. They concluded that careful consideration should be given to procedures for the rejection of outliers, and that many analysts should pay more heed to establishing the accuracy of their results, rather than merely attempting to improve precision.Plesch (361) reviewed the AAS results from several laboratories for 8 trace elements in drinking waters. He concluded that of the 8 elements studied only Zn and possibly Cr could be determined with sufficient accuracy to comply with the 1975 EEC regulations for analysis of drinking waters; all could be determined by XRF however. Knechtel et o f .(414) conducted an inter-laboratory programme to select the best technique for the analysis of sludges, the methods investigated including AAS, AES, XRF and NAA. Comparison of results by different methods within a laboratory is less reliable than inter-laboratory comparison, but can give a guide to accuracy. Beckett (1072) compared results for 73 elements in sludges obtained by techniques including AAS, emission spectrography, spark source MS and y-photon activation.Similarly, Capar et d. (1171) used up t o three methods to measure each of 30 elements in sludges, including flame and hydride AM, PCP-OES and ASV, and found the general agreement to be fairly good in most cases. Baudin (37'6) compared AAS, OBS and various other techniques for the analysis of drinking water, sea-water and industrial waste water.Criteria examined included storage, in-situ analysis, pre-concentration, choice of method, selectivity, analysis time and accuracy. Of growing interest in the environmental field i s the question of speciation of trace metals. Mercury speciation in sludge and water samples i s of considerable importance.Grimm et al. (33'3) were able to distinguish between methyl and dimethyl Hg at levels down to 30 ppb in sludges by combining GC with AAS. Baltisberger (31 3) developed an ETA-AAS technique able to differentiate between inorganic and organic Hg cations in theChapter 4: Applications 125 range l&lOO ppb in aqueous samples. Speciation of Pb i s important in atmospheric studies; Robinson and Kiesel (3'07) used a GC-AAS method with ETA to investigate organic Pb in filtered air. Reamer et aZ.(60) used GC, with a microwave plasma OES detector, to measure tetra-alkyl Pb and alkyl Se in air. ETA-AAS has been used for water samples to distinguish Se(IV) and Se(VI), either after solvent extraction (426) or after hydride generation (887)' and Cr(II1) and Cr(V1) after separation by solvent extraction (517).An HPLC system using an AAS detector has been used by Coleman and Koropchak (100) to distinguish CdSO, and CdBr, in water, while Aue and Flinn (330) have described a flame photometric Sn detector for the determination of organo-tin compounds after separation by GC. 4.5.2 Water Analysis 4.5.2.1 Sample PreparationlPretreatment.In comparison with other sample types, the degree of sample preparation needed with waters is normally relatively small and the main problem is usually that of satisfactory storage. Dellenbarg and Church (238) compared results obtained from estuarine samples, immediately extracted at sea, with those following various storage procedures. Only samples that had been filtered (<1 pm), acidified, and stored frozen gave similar results. Stoemler and Matthes (1390) found it necessary to determine inorganic Hg in sea-water immediately on collection, whereas for methyl Hg chloride the samples could be stored for up to 10 days in brown glass bottles with rigid plastic screw caps.Subramanian et al. (1 96) cornpared various techniques for preserving trace metals in synthetic and natural water samples, the most effective being acidification to <pH 1.5 and storage in 'Nalgene' containers.The filtration of water samples, either before or after storage, raises the problem of exactly what should be considered as 'dis- solved'. It was shown for filtered reservoir samples (624) that the use of 0.2pm Nucleopore membranes was preferable to 0.45pm membranes, as the latter allowed passage of some clay sized particles. Additional preparation of water samples may be necessary for the determination of organometallic species.Farey et al. (529) described a rapid breakdown procedure for organo-mercury compounds using brmination with a KBrO, / KBr solution, the excess of Br, being reduced with hydroxylammonium chloride.Preparation of sludges and sediments usually involves the complete destruction of organic matter, although less time-consuming extraction procedures may also be used. Three extractants (dilute HNO,,, 1 M NH,Cl, H202) and density separation using bromoform were tested (620) on clays spiked with Cu and Pb; none of these procedures appeared to be completely satisfactory.Rees and Hilton (Lab Pract., 1978, 291) compared traditional HNO, /H,O, digestion of sewage sludges with the rapid extraction of heavy metals using HCl/H,O,. FAAS determinations showed similar precision and similar or higher recoveries by the more simple extraction procedure. Agemian and Chau (1 389) compared four extraction procedures €or heavy metals in aquatic sediments using FAAS.They found 0.5M HCl most satisfactory, although O.OSM EDTA at pH 4.8 gave similar results. Delfino and Enderson (1071) compared five techniques (HNO,, HNO,/H,O,, HNO, /HC1, dry ashing at 550 "C, and r.f. ashing) for 13 elements in sludges and found no large differznces in results. In a comparison (1095) of HF/HCl digestion with LiBO, fusion, for the determina- tion of Ca by FAAS in lake sediments, both techniques produced very variable recoveries.Scott (534) showed that loss of Cr during HNO,/HClO, digestion of aquatic sediments is not due to volatilization of CrOCl,, but can be attributed to adsorption of Cr on the silica residue, Dissolution of the residue with HF avoided the problem. Kozuchowski (1396) combusted sediments at 870 "C in an 0, atmosphere and collected the released Hg in a trap of Au-coated glass beads.The Hg was subsequently released by heating the beads at 500 "C in He and determined by an emission technique using a d.c. discharge. Preconcentrcrtion by solvent extraction continues to be of importance in water analysis1 26 A naly tical A tomic Spectroscopy and many new reports on the technique have appeared during the past year.Most of these use a dithiocarbamate as complexing agent, either APDC or Dim, with a variety of organic solvents. The need for caution in the application of such techniques is becoming increasingly apparent. In the last review the problem of incomplete extraction in the presence of natural organic compounds was discussed (ARAAS, 1977, 7, 147); the poor stability of the extracted complexes i s now more widely recognized and many recent applications have avoided direct determinations on the extract solutions.The usual alternatives are evapora- tion to dryness followed by dissolution in 0.1M HNO, (269), or back extraction into dilute HNO, (886, 915). Sperling (1461) found that the APE/MIBK system was effective for Cd in sea-water provided CCl,/C,Cl, was used as solvent for both, the reagent and its Cd complex.Two further extensive studies of the APDC/MIBK system have been made for trace metals in potable waters (1348) and sea-water (1359). Other preconcentration techniques have also been reported. Several workers have used co-precipitation methods, such as collecting As using Fel(OH), (599, 1075), Cr using Fe(OH), (1395), Cd, Co, Cr.Cu, Ni and Pb using Fe(OH), or the Fe complex with APDC (885) and Hg using PbS (494). Wasco and Fasching (185) used the adsorption of trace. metals onto controlled-pore glass beads under alkaline conditions followed by release into dilute HNO, to achieve separation from the matrix. Tests for Pb and Cd in artificial sea-water resulted in complete separation from the matrix and excellent recoveries (90-100%).Ion-exchange concentration continues to be of interest; Horvath et al. (40) used iminodiacetic acid ethyl cellulose, a chelate-forming ion exchanger, to obtain 1- to 20-fold concentrations of Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb and Zn in various waters. Alder and Das (573) used an Amberlite IRC 50fH) column to concentrate U prior to its indirect determination.Automated sample preparations have been described by several workers. A flow- through U.V. digester system has been used to degrade organo-mercury compounds for the determination of Hg in fresh and saline waters at a rate of 30 samples 11-1 (639). This was said to avoid the interference of chloride on the cold-vapour AAS determination, which occurs using automated chemical oxidations.The latter (using persulphate oxidation followed by stannous chloride reduction) has, however, been reported (641) with a similar throughput of Hg in sediment samples. Pyen and Fishman (705) reported the analysis of Se in 150 or more water samples per day using a dry-block persulphate digestion Auto- Analyzer chemical treatment, with heated tube hydride generation and ETA-AAS deter- mination.An automated hydride generator was also used (664) in a system capable of analysing 20 samples h-1 for Sn, down to 0.001 pgml-1, in water. Pierce and Brown (10) described a semi-automated system using ion exchange followed by AES to determine Ba and Sr in surface water samples at the rate of 40 samples during a IlO~min run.Fleming (1377) described an automated continuous flow system for on-line monitoring of Mg in boiler feed water by non-dispersive AFS. 4.5.2.2 Atomic Absorption Spectroscopy. Reports of improvements to conventional FAAS methods for water analysis are now relatively rare, although interest in investigating inter- ferences continues. Rawa and Henn (1260) showed for Cr in water that, as with many other 'real' samples, the use of the N20/C,H, flame is essential to combine adequate sensi- tivity with freedom from interferences.Losser (703) found that results for Fe in marine sediment leachates were unacceptably low unless an addition of 0.5 NH,C1 was made; it was postulated that the latter acts as a protective agent removing cationic interferences. The applications of electrothermal atomization to water analysis continue to increase.Sheaffer et al. (914) described a technique that allowed the determination of Ag in 1 ml samples of rain or melted snow, Batches of graphite furnace tubes were precoated with paraffin (to prevent spreading and seepage into the graphite), and maintained at 80 'C on a hot-plate while 20 successive 50-pl injections of sample were added to each.The detec-Chapter 4: Applications 127 tion limit for Ag was given as 1 X 10-6 pg ml-1 with a precision of better than 2 20% for triplicate analyses. Several workers have described procedures for pyrolytic graphite coating of ETA tubes. Lagas (519) found that use of the correct coating temperature, together with addition of an optimal quantity of La during coating, improved reproducibility and reduced memory effects for the determination of Be, Ba and V in surface and tap waters. Matrix interference problems in ETA-AAS remain of concern, although the number of publications in this area is small for water samples.Ohta and Suzuki (1144) investigated a selective extraction of As from Bi, Cu and Sb as the thionalide complex and found that the presence of S-containing agents in a Mo-microtube atomizer enhanced the As atomisation and pre- vented interferences by most of the 14 accompanying elements found in river and sea-waters.Regan and Warren (521) observed that ascorbic acid was useful for reducing interferences in the determination of Pb in drinking waters, although certain types of samples still showed interference.Automation of AAS determinations continues to be of interest in water analysis, either by the use of automatic sequential analyzers for multi-element determinations or simply by the addition of microprocessors to provide computer calculated calibrations with curve correction. The advantages of the latter in water pollution measurements have been pointed out by Routh et al.(13’9); pollutant concentrations varying by several orders of magnitude can be measured quickly and precisely with one set of instrumental conditions as a result of the extended AAS working range achieved using microprocessor electronics. An unattended AAS water monitoring station has been described (328), each sample being automatically analysed for 7 elements (Cd, Cr, Cu, Fe, Mn, Pb and Zn) in 21 min.Skogerboe et al. (939) have described the analysis of water samples using simultaneous multi-element AAS in which several spectral line sources were multiplexed and a photodiode array used as the detector. Nakajima et d. (208) described an automatic system for heavy metals in waste waters, while Stoeppler (595) discussed the possibilities of using computer control for sampling and AAS determinations of Cd, Cu, Ni and Pb by ETA.The indirect determination of non-metals by AAS continues to be of interest. Le Bihan et d. (12) have imprwed earlier FAAS methods (Analusis, 1973, 74, 695) for detergent determination by using smaller sample volumes and ETA. Anionic detergents in water were extracted into MIBK as the detergent-tris( 1,lO-phenanthroline) Cu(I1) complex and the Cu determined directly by AAS.Non-ionic detergents of the polyethoxylated type were extracted into benzene as the ammonium cobalt thiocyanate complex. Glaeser et al. (859) determined long-chain primary amines (e.g., octadecylamine) in cooling waters by extraction into nitrobenzene as amine-chromate ion complexes. Organosilicon compounds in sewage sludge have been determined directly (1251) in MTBK solution after clean-up by passage through active charcoal.Phosphate in sea and river waters was determined (580) by co-precipitation with Al(OH), and extraction into butanol as a phosphomolybdate complex, the Mo being measured directly by AAS. 4.5.2.3 Atomic Emission Spectroscopy. As mentioned in Section 4.5.1, watcr analysis by AES is now experiencing a major revival of interest as a result of the availability of inductively coupled plasmas with large multi-element spectrometers.Using such a system, Ronan and Kunselman (4‘80) were able to analyse a surface or waste water sample every 30s for 23 elements, giving a capability of thousands of elemental analyses per man day. Garbarino and Taylor (657) have suggested that high accuracy i s unnecessary for many trace metal in water surveys and have used an ICP-OES system with computer software which rounds off the concentrations of 30 elements to appropriate ‘reporting levels’.Taylor (201) has investigated factors affecting the reliability of ICP-OES for watcr analyses, particularly relating to Ca and Mg determinations, and after comparing the accuracy and12s Analytical Atomic Spectroscopy reproducibility with that of data obtained by spark source MS, concluded that the technique was precise, rapid and accurate. The problems of automating commercial ICP spectrometers for natural water analysis have been discussed (1426, 1427).Interest has also been shown in the use of other types of source for OES, particularly the d.c.arc argon or heZiurn plasma. Taylor and Skogerboe (938) have compared results for natural water samples, obtained by using the latter source with an cchelle grating spectrometer, with those produced by an Ar ICP with a computer-controlled direct-reading spectrometer. Ball et al. (888) used a d.c. Ar plasma and echelle spectrometer to determine B in a variety of natural waters at levels from 002-250 pg ml-1; the results were reliable provided frequent recalibrations of the spectrometer were made and matched standards used for sea-waters.Braman and Tornpkins (951) madc a detailed study of interference effects when using hydride generation with a d.c. He plasma to determine Sb and Ge in environmental samples. Several workers have used electrothermal atomizers for emission measurcments and comparisons have been made of the relative merits of AAS and AES determinations under otherwise similar atomization conditions.Epstein et al. (849, 91 1) concluded that a satisfao tory evaluation could only be made for individual elements in particular samples. Hobbs (759) has described the use of a microwave plasma emission detector with a GC system for the determination of chlorinated hydrocarbons in water. 4.5.3 Air and Atmospheric Particulate Analysis 4.5.3. I Sample Preparation /Pretreatment. Dreesen et al. (482) compared various extractants (HNO,, HC1, citric acid, H,O and aqueous NH,) for their effect on coal fly ash samples. They found a positive correlation between decreasing extraction efficiency and increasing pH for As, B, Be, Cd, Cr, Cu, F, Se, V and Zn, but not for Mo.McDonnell and Hilborn (1210) compared alkali fusion and HNO, extraction for Pb particulates on glass-fibre filters; the wet procedure gave better precision but recoveries of some Pb compounds (PbO, and PbS) were significantly higher using the fusion technique. Chelation concentration systems have been studied (54) for Cd and Ni in HNO,/HC10, digests of air-filter samples. Good results were obtained with Ni using a 100 : 1 preconcentration with 1-nitroso-2-napthol in MIBK, but reliable results could not be obtained for Cd.TOPO-MIBK has been used (1231) to extract Sb from H,SO, solutions of air-filter digests. Degan and Haerdi ($19) were able to determine Hg down to 1 ng by ETA-AAS after preconcentration on a micro-column of silver wool.Yamashige et 01. (1375) used ion-exchange to separate Se from extracted air particulates prior to AAS determination as the hydride. 4.5.3.2 Atomic Absorption Spectroscopy. A novel method of determining Hg vapours in laboratory atmospheres has been described by Tyson and Kaseke (731). The Hg was trapped as an amalgam on carbon rods coated with Ag or Au before direct atomization in an ETA, the detection limit being about 90 pg.Newstead and Whiteside (123) reported that the direct determination of Be on atmospheric filters is possible provided that adequate background correction is available. Kovatsis (967) determined CS, in air indirectly by FAAS. The CS, was trapped in a solution of Zn acetate and N,N-dibenzylamine in methanol; the Zn dibenzyl dithiocarbamate formed was then extracted into toluene for determination of the Zn in an air/C,H, flame.Most other reports in this area were concerned with investigation of interferences occurring in ETA measurements, Denyszyn et al. (952) found that As determinations (after collection on charcoal and dissolution in acid) were improved by the addition of Ni to stabilize the As.Carelli et al. (496) measured Sb in air by ETA after extracting the filters with HNO,, evaporating, redissolving in HCl, adjusting to pH 7 and adding tartaric acid and Triton X-100. Sutter and Leroy (230) showed that HNO, interferes with determinationsChapter 4: Applications 129 of Ni and V in airborne particulates.Cohen and Kurchatova (497) found that interferences of PO,3-, C032-, I-, F- and CH,COO- on determinations of atmospheric Pt could be avoided by adding 0.1M EDTA to the HNO, solutions. 4.5.3.3 Atomic Emission Spectroscopy. Several workers have investigated the microwave (2450 MHz) plasma as a source for AES measurements on air samples. Hanamura (176) used the air being sampled as the plasma gas (at atmospheric pressure): the system was similar to that normally used with low pressure Ar plasmas except that a Pt electrode was placed in the torch to reduce the power needed to maintain a discharge.The sensitivity was adequate to monitor Pb concentrations of 5pgm-3 in air with an absolute detection limit of about 1 pg. Hobbs (157) and Zoller and O’Haver (1007) have used microwave plasmas as GC detectors, the former to monitor organic volatiles collected in an industrial environment and the latter for monitoring tetra-alkyl Pb spccies collected from the atmosphere.Braman ei al. (912) used a flame photometric detector to determine H,S and organo-S compounds collected on Au-coated glass beads from coastal air. Detection limits in a H2 diffusion flame were about 0.01 ng or 0.1 parts per 1012 V / V for 100-1 samples.Table 4.5A AIR AND PARTICULATES Element X/nm Matrix Sampte treatment Atomization Ref.Concentration Tech. Analyie form As Be Be Cd Cd Cd Ge Hg Hg Mn Mn NI Ni Ni 193.7 Air 1-10 pg/m3 - Airborne particulates 234.9 Airborne particulates 228.8 Airborne par:iculaies 228.8 Aiborne par.icula!es - Air 265.1 Air 253.7 Labora:ory airnospheres - Air.water - Air - Airborne particulates - Airborne particulates 232.0 Air borne particulates - Welding fumes 7.5-775 ng/ni3 (in air) Trace levels - 3-48 ng (absolute) 0.1-2 ,ug/rn3 From 1 ng (absolute) 0.002-0.22 fig/m3 0.5-1 1.8 ng/mJ ( i n air) - 0.1-1 mg/m3 A .4 A A A A E A A A A A A A L S s, L L L L L, G L, G G L L L L L Collect as ASH, on charcoal, extract wilh acid and add Ni before introduction to ETA Study of background correction system Graphite furnace - Graphite furnace Wet-digest filter samples with 1:l Graphite furnace 14NO3/HCIO,.Neutralize and apply directly to furnace. See aiso Ni, ref. 54 (Extractlon- concentration method not successful for Cd) Collect on PVC filter, extract with F Air/C,H, HNO,.evaporate to dryness and Graphite furnace re-dissolve in HNO, - Graphite furnace Collect Ge and/or me!hyl-Ge compounds P D.C plasma in acid solution (pH 1.5) and reduce with NaBH, Collect Hg by amalgamation with Ag Graphite furnace or Au electro-deposited on graphite rod Pre-concentrate on. Ag microco:umn Cold vapour Graphite fUrnaCe (HGA-2100) - Graphite furnace (methylcyclopentadienyl manganese tricarbonyl) from vehicle exhausts Wet-digest filter sample with 1:l HNOJHCIO, neutralize and extract Ni with 1-nitroso-Bnaphthol in MIBK.See also Cd, ref. 54 Meihod for detection of MNT F - Graphite furnace Interference study Graphite furnace (IL-455) - Graphite furnace 952 123 1250 54 497 81 3 951 731 81 9 a13 1209 54 230 752Pb - Air From 60 pg (absolute) E G Combined GC/microwave plasma P hilicrowave 60 2 Pb 405.7 Air (automobile exhaus:s) From 5 m/m3 E G Collect sample (20 I) in plastic bag P Microwave 176 $ 5 b (Pt electrode) ctr as :e:ramethyl Pb detector system plasma plasma in air and introduce to plasma by pumping Fb 217.0 Dus?s 283.3 12-200 pg/ml A.L Dry at 120 "C, sieve and grind. Boil 1 g F Air/C,H, 245 (in extract) sample with 10 ml 2M HNO,, filter n* 2 x, and dilute, with addition of EDTA.Dithizone/CHCI, extraction (pH 9.5) also employed orgar7ic Pb levels From 1 ng/ms A L, G Study of relative inorganic and Graphite furnace 307 Pb Pb 283.3 Air 283.3 Atmospheric particulates A L Graphite furnace Coiles! on Millipore filter, treat successively with HNO,, HN0JHCI0, (HGA-74) and HF, evaporate to low bulk and prepare final solution in HNO, - F Delves cup 421 Pb Pb A L A L 430 497 - Airnospheric particulaies 21 7.0 Airborne particulates 3.4 :1g/m3 - See Cd, ref. 497 F Air/C,H, Graphite furnace Pb A L Study of sampling and dissolu!ion F - methods Collect Pb fall-out samples directly Graphite furnace with graphite cup 506 - Air 25-250 ,ug/mJ 0.23-3.7 pg/m' (urban) (control) A L 594 898 Pb - A:r 81 3 1007 Fb F:, - Air 405.7 Air A t E G - Graphite furnace GC/MIP method for tetra-alkyl-Pb P MIP species Review (263 refs.) F, A - Collect on micropore filter, char in F Air/C,H, Ta cup at 200-250 " C and ash i n air at 350 "C Collect on 2 graded Nvclepore filters, F - ;o sr-para'e respirable and non-respirable Pb, and extract with HNO, +Ta cup A, E L A L 1104 1136 Pb Pb - Environmental samples - Airborne particulates - 0.3-1 .O pgjrns 1208 Fb - Airborne particulates 0.1-1 pg/m3 A LTable 4.5-4 AIR AND PARTTCuLATEs-conrii~ued _ _ _ _ _ _ ~ ~~ ~ Element X/nm Matrix Conceniration Tech.Ana'yte Sample treatment Atomization Ref. form Pb 283.3 Sb - Sb Sb Se Se 252.8 - - 196.0 Airborne particulafes Air Air Industrial airborne particulates Air Airborne particula:es Air Airborne particula!es From 0.01 ng (absoluie, i n 101) I sample) 1-10 yg (absolute) From 0.2 mg/m3 2-41 ng (absolute) From 1 kg/ml ( i n extract) From 20 pg (absolute) as dimethyl Se (absolute) 0.1-5.0 ,/ig L G L L L, G L G 0 Collect sample (approx. 0.2 g) on F Air/C,H, 1210 glass-fibre filter. (A) Extract with HNO, ( 1 : l ) under reflux (B) Fuse with alkali at 900 "C and extract with HNO, Colect H,S and organo-S compounds F Air/H, 91 2 by drawing sample over Au-coated giass beads.Heat and collect vapours i n liquid-N, trap. Heat and sweep final sample in stream of H, to diffusion flame Trap CS, in Zn acetate solution in F Air/C,H, 967 methanol + "1-dibeiizylamine. Add H,O, extract with toluene and measure Zn Collect sample on Millipore filter Graphite furnace 496 (0.45 prn) extract wiih HNO,, evaporate io dryness, dissolve in HCI, dilute and adjust to pH 7 with NH,OH. Add tnrtaric acid, boil, add 1 drop Triton X-100 and dilute to volume See Ge, ref. 951 P - 951 Collect on filter, extract with F - 1231 b HNO,/H,O,, filter, evaporate and dissolve "C See Pb, ref. 60 P Microwave 60 ' M s. in H,SO,. Extract from Kl/ascorbic medium with TOPO/MIBK 2.$ plasma Dissolve filter sample i n HNO,/H,O, Heated SiO, cell 1375 and evaporate extract to dryness. (950 "C) Dissoive in 0.05N HNO, and pass through Dowex 50 W-X8 column. Evaporate effluent, dissolve in 3.5N HCI and reduce with Zn. Pass H,Se to heated cell r/l 2 s 2 0 '0 '4V 318.4 Airborne par!iculates - Various - V s.r i o u s - Various d Variom - Various d Various - Various - (7) Air - Airborne particulates - Airborne particulates - Airbor2e particulates ng levels (absolute) Airborne particulates - Indus?rial airborne - particu:ates Air - Air - Airborne material - A L E G E L A L A L A L, s A L.S A L A L, s A L See Ni, ref. 230 Graphite furnace (IL-455) Combined GC/microwave plasma P Micro:*rave aetectcr system. Possible elements: C, H, D, 0, N, F, CI, Br, I , P, S, Se, As, Hg and Pb Comparison of ICP and XRF results P ICP on air particulate standard reference ma!erials Paper filters are preferred to glass fibre F - filters Treat 10 cm2 filter paper with hot HNO, F Air/C,H, fo:lowed by HCIO,.Evaporate and redissolve in HNO,. Determine Zn by FAAS and Cd, Cu, Fe, Pb by ETA-AAS - Graphite furnace plasma Graphite furnace (HGA-74) Review (23 refs.) d d Comparison of FAAS and X-ray F - speciroscopy (for Mn, Fe, t n , Pb) Review of methods Graphite furnace Results given for Mg, V, Fe, Ni, Cu, Cd F and Pb in New York City aerosols - 230 $ I57 ct % 2 $ ?? b 189 3. 209 2 229 321 432 838 1201 1211 c w wl-l Table 4.5B WATERS, SEWAGE AND EFFLUENTS form x Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Ag - Sea-water 0.04-0.1 pg/l A Ag - Waters, fish Ag 328.1 Snow, rain - A 0.1 ng/ml level A As - Waters, effluents pg/l levels A As 193.7 Natural waters 1-12 p g / i A As - Well water 1-13 pg/I A As As As As 193.7 Municipal was% materials Up to 100 p g / g A - Water 193.7 Waters 189.0 Waters 193.7 From 1 ng/ml A 0.5-20 pg/i A A - L L L L G L L G L L Extract 1000 m l sample with 4 ml 2% Graphite furnace DDC solution and 20 m l CHCI,.Repeat and evaporate combined organic phases to dryness. Redissolve in 1 ml 0.1M HNO, Extract with AP DC/M I BK F - Acidify samples with HNO, and freeze until tequired. Concentrate sample by sequential evaporation, at 80 "C, of 20 50 pi aiiquots i n furnace tube Comparison of AAS, polarographic and F - colorimetric methods Hydride-evolution method, with liquid- Graphite furnace Acidify with HCI at time of sampling.F Ar/H, Add FeCI, solution, adjust to pH 7-70 with NH,OH, filter and dissolve precipitate in 4N HCI. Reduce to ASH, with KI/Zn/SnCI, Add Mg(NOj)2 + Ni(NO,), + at 450-500 "C. Add H,O/HNO,, evaporate t o dryness, treat with HF/HNO,, again evaporate and redissolve in HN0,/H,02 Reduce with NaBH,, to form ASH, Co-precipitate with Fe(OH), at F Ar/Air/H, pH 8-9.Separate by flotation and dissolve i n HCI. Reduce with NaBH, Add K l + H,SO,, followed by 0.1M Na,S,O, solution and extract As as thionalide complex into isopropyl ether Graphite furnace N, trap (HGA-2100) Graphite furnace C,H,OH. Dry gently and finally ignite (HGA-2100) Heated SiO, tube (950-975 "C) + SiO, tube Heated Mo tube 269 622 914 31 2 51 8 551 569 L x 5 i x -. 818 5 1075 k 5 3' b 1144 2 5 c? c,B 249.8 Sea-water Trace levels A B 249.8 Natural waters 0.02-250 pg/ml E Ba 455.5 Surface waters 0.012-1.14 mg/l E Ba Ba Ba Be C Ca Ca Ca Cd ( co, 1 - 553.6 553.6 234.9 - (Ca) 422.7 - - 228.8 Po:ab!e waters, sediments 0.01-0.20 mg/i Waters 35-100 p g / l Sea-wa;er Up to 30 pg/l Waters 0.1-0.3 pg/l Waters - Lake sediments - Waters; sewage effiuents Rain, snow - Water 200 mg/I level Up to 40 yg/ml Cd - Sea-water 1 pg/l level A Cd - Sea-water Cd - Lake waters 0.01-0.03 hg/I A A - Cd - Wate:, sediments - A L L L L L L L L L L L L L L L L Prepare as 3M H,SO, solution and F N,0/C2H2 228 $ extract with 2-ethyl-1,3-hexanediol Add L i buffer solution.Match P D.c. argon 888 5 s:andards for sample matrix plasma Adjust to pH 3 with HCI, using F N,0/C,H2 10 methyl yellow indicator. Automated cation exchange system then removes Ca and other ions and separates Ba, Sr for analysis Acidify with 0.6 ml conc. HN0,/100 ml Graphite furnace 224 2 - Graphite furnace 519 ? 2 =: 2 6. sample, on collection (HGA-72) (HGA-74) Graphite furnace 570 Graphite furnace 519 (HGA-BOO) (HGA-74) - F - 1142 Ash at 600 "C and either digest with F Air/C,H, 1095 HF/HCI or fuse wth LiBO, Acidify and add La salt F - 1232 F Air/C,H, 1311 Combined LC/FAAS system, t o F Air/C,H, 100 investigate characterization of metal compounds in sample, e.g., CdSO, + CdBr, Adsorb Cd, Pb on prepared glass beads Graphite furnace 185 solution.Filter, wash and dissolve metals with dilute HNO, See Ag, ref. 269 Graphite furnace 269 N,O/C,H, - (Bio-Glas-200) i n ammoniacal (HGA-2000) Graphite furnace 621 (HGA-72) (A) Waters-acidify with HCI F - 624 (B) Sediments-Dry at 105 "C, sieve (80-mesh) and digest with HNO, - wTable 4.5B WATERS, SEWAGE AND EFFLUENTS-contirzued ~~ - ~ - Element X/nm Matrix Concentration Tech.Ana'yte Sample treatment Atomization Ref. form Cd 228.8 Waters Trace levels A Cd - Waste waters - A Cd 228.8 Water Cd 228.8 Sea-water ng/ml levels A - A c o 240.7 Waters Trace levels A Cr 357.9 Natural waters - A Cr 357.8 Waste waters 0-5 m g j l A Cr Cr 357.9 Sea-water 357.9 Aquatic sediments Cr - Water Cr 357.9 Wster Cr - Water 0.02-3.3 &g/i - A A 5 ,ug/ml level E Trace leve!s A From 0.05 pg/ml A L L L L L L L L L L L L Concentrate impurities by coprecipitation with APDC or Fe(OH), and redissolve in HNO,. Evaporate to dryness and dissolve in H,SO, Acidify, boil and either aspirate directly, or, for low levels, extract with APDC/MIBK Acidify with HNO, Modification of APDC/MIBK method, using CCI, or C,CI, solvent for reagent See Cd, ref. 885 Method for determination of total Cr, C r ( l l l ) and particulate Cr To 30 mi sample, adjusted to pH 1.7 with mineral acid, and containing 0.5-50 Mg Cr, add H,02 + 10 ml MIBK.Shake for 1 min. and separate organic phase (A) Cr(Vi)-extract with Aliquat-336 in toluene, from solution at pH 2 ( 8 ) Cr(1II)-extract from solution at pH 6-8, in presence of thiocyanate Digest with HNOJHCIO,. Filter off any insoluble residue and treat with HF/HNO,.Determine Cr in both extracts Add 2.5 pg/ml TI and Li, as buffers and also 5% C,H,OH t o enhance sensitivity. Use graphite electrodes See Cd, ref. 885 Study of flame conditions Graphite furnace (HGA-70) F - Graphite furnace Graphite furnace ( FLA-100) Graphite furn,ace Graphite furnace F Air/C,H, (HGA-2100) Graphite furnace (HGA-72) A - Graphite furnace F N,O/C,H, 885 1195 1372 1461 885 1395 232 517 5 a x -. 534 $ 3 ;i' 668 h 2 1260 $ 'r; 885 2Cr 352.0 Sewage sludge - c u - Natural waters - A L A L c u - Saline waters Trace levels A L L L c u c u - Sea-water - Sediments 0.4-1.2 &g/l - c u cu c u cu c u - Lake waters 324.7 Water - Water - Waste waters - Lake sediments c u 324.7 Water Fe - Saline waters Fe - Water films and surface foams Trace levels Trace levels A A A L A L A L A L A L ng/ml levels A L Trace levels A L - A L Digest with HCI/HNO, F Air/C,H, N,O/S2H2 Study of speciation of trace metals, F Air/C,H, based on a pH titration/size Graphite furnace Filter, acidify and store frozen.(S:udy F Air/C,H, of sample s!orage. Results compared Graphite furnace with those given by on-site extraction with APDC/MIBK) See Ag, ref. 269 Study of extraction procedures, using F Air/C,H, model sediment (Bentonite, MnO,, humic separation procedure (HGA-2000) (CRA-63) Graphite furnace acid) : (A) Dilute HNO, (8) 1M I\IH,CI (D) Density separation (with CHBr,) (C) H,O, See Cd, ref. 885 Application to geological surveys See Cd, ref. 1195 Determine Cu, Fe, Mn, Zn in fractions obtained by successive extraction with (A) 1.OM acetic acid, (B) 0.lM HNO,, (C) acidified H,O, (pH 2) -t 1.OM NH, acetate in 6% HNO,, (D) 0.25M NH,OH.HCI in 25% acetic acid (E) HNO,/HCIO,/HF (3:2:5) See Cd, ref. 1372 See Cu, ret. 238 Graphite furnace Graphite furnace Graphite furnace (HGA-72) F - F - Graphite furnace F Air/C,H, Graphite furnace (FLA-100) (CRA-63) F - 1313 199 238 269 620 62 1 885 940 1195 1309 1372 238 61 9Table 4.5B WATERS, SEWAGE AND EFFLUENTS-continued - W ~ ~ ~ _ _ ~ __ Element X/nm Matrix Concentration Tech.Sample treatment Atomisatlon Ref. form - Water 5 ,ug/ml level E 305.9 Marine sediment leachates 50&4600 pg/ml A - Water 0.25 ng/ml - Lake sediments - 265.1 Waters - - Waters 10-100 pg/l - Sludges, sediments From 30 pg/l I Natural waters - - Sea-water - - Mineral waters pg/l levels - Waters, sewage, effluents - A 253.7 Fresh and saline waters 0.02-0.7 ,ug/l A - Aquatic sediments From 0.1 mg/l A - Waters ng/l levels A - Sea-water - A L L L L L L, G G - G L, s G G G G G See Cr, ref. 668 Digest with 5N HNO,, wash, centrifuge and dilute with 5N HNO,. Dilute for analysis with addition of NH,CI Pre-concentrate by evaporation See Cu.ref. 1309 Hydride-generation method, using liquid-N, trap Method for differentiation of organic and inorganic Hg Combined GC/AAS system - - Co-precipitate Hg with PbS, by addition of Pb acetate + Na,S to sample made acid (pH 1.0) with HNO,. Decant, wash residue with H,O, dry at 50-60 "C and excite in Fe electrode Add HCI + KBrOJKBr solution and shake. Add 1-2 drops NH,OH.HCI + NaCl and dilute.Reduce with SnCI, Preserve samples by addition of H,SO, + K,Cr,O,, using glass vessels. Method includes u.v.-digestion stage Add dichromate preservative solution to samples. Oxidize with K,S,O, and reduce with SnCI, Oxidize with K,S20, + H,SO,, add SnCI, and pass vapour in stream of air or argon to Ag-wool trap. Release Hg by rapid furnace heating Study of sample storage behaviour A - F Alr/C2H, Graphite furnace F - P D.c.plasma Cold vapour (He) Cold vapour - - Cold vapour A 10 A a.c. Cold vapour Cold vapour Cold vapour Cold vapour Cold vapour 668 703 1279 1309 951 31 3 333 410 412 494 529 b 639 & 3 x k 3 748 0 B ? -. 64 1 k -. cr, 1390 5Hg Hg K K L1 L i Mg Mg Mn Mn Mn Mn Mn Mo Na Ni NI P (PO,) Pb Pb Pb Pb Pb Pb Aquatic sedimenis Liquid effluents Water Rain, snow Natural waters Waters Rain, snow Boiler and feed waters Water films and surface foams Water Water Lake sediments Saline waters Water Rain, snow Waters Waste waters Sea-water Sea-water Drinking water Sediments Lake waters Waters.sediment8 Water Up to 100 ng (absolute) 1-10 pg/ml I 500 pg/l level - I 0.01-3 ,ug/ml - 0.5 pg/ml level - - - Trace levels - Trace levels - Trace levels - 5 pg/ml level E A E A A A A F A E A A A A A A A A A A A A A E G G L L L L L L L L L L L L L L L L L L L L L L Heat in O, at 870 "C and collect P - 1396 2 Fig on Au-coated glass beads.Heat at 500 "C in H e flow - Cold vapour 1403 $ % > L Study of Na interference F - 1134 Add Na (1000 pg/ml) F Air/C,H, 1311 Dual-beam AAS system, monitoring F - 92 $- bLi/7Li abundance ratio Y - Graphite furnace 448 - F Air/C,H, 1311 Add La salt F - 1377 - F - 61 9 b See Cr, ref. 668 None See Cu, ref. 1309 - See Cu, ref. 940 - See Cd, ref. 885 See Cd. ref. 1195 Co-precipitate PO,- ion with AI(OH),, extract into butanol as phospho- molybdate complex and measure Mo See Cd. ref. 185 Adjust to 0.15M HNO, strength and add ascorbic acid See Cu, ref. 620 See Cd, ref. 624 See Cd, ref. 668 A - Graphite furnace F - Graphite furnace Graphite furnace F Air/C,H, Graphite furnace F - F - Graphite furnace Graphite furnace (HGA-2000) (HGA-72) F - Graphite furnace (HGA-72) F - A - 668 885 1309 1361 940 1311 885 1195 580 185 52 1 620 621 624i5 Table 4.53 WATERS, SEWAGE AND EFFLUENTS-continued Element X/nm Matrix Concentration Tech.Sample treaiment Atomization Ref. form Pb 283.3 Water Pb - Waste waters Pb - Water Trace levels A - A - A S - Waters Trace levels E Sb 206.8 Municipal waste materia!s Up to 100 Ng/g A Sb - Geo?hermal waters Sb 252.9 Waters Se 196.1 Water Se - Se I Sn - Sn - Water Water Sewage sludge Environmental samples Water, s?reambed rna!er iais Sr 460.7 Surface waters Sr 460.7 Water From 6 Fg/I A - E 240 ng/ml A - A A Trace levels E From 1 gg/l (waters) A From 0.1 gg/g (others) 0.0'35-1.02 mg/l E 0.02-0.28 mg/i A L L L L L L L L L G L G G L L See Cd, ref. 885 Method for detection of organo-Pb antifouling paints MECA method See As, ref. 569 See Ge, ref. 951 Stcciy of extraction procedures, using DDC, APDC and dithizone. Final method differentistes Se( I V ) and Se(VI) Add KLSL08 + HCI, boil and dilu:o.Generate Se hydride by addition of SnCI, + K I + NaBH, Generate H,Se evolution with NeBH, and collect gas in liquid-N, trap. Release in s'ream of Ha. Modifications given for speciation of Po compounds Adjust to pH 6-7 with NaOH or HCI, extract with toluene and evapora:e. Redissolve in MIEK, pass through activated C column and measure Si (Me:hod for dimethylpolysiloxane) GC + flame detector system Add EDTA to remove inLerferences and generate SnH, by addition of NaBH,.Pass vapour to atomizer in &ream of N, See Ba, ref. 10 Add 1 m l conc. HNO, to 200 ml sample, evaporate to dryness, dissolve i n HNO, and add LaCI, Graphite furnace F - F - F - Graphite furnace (HGA-2100) F - P - Graphite furnace (FLA-10; HU-10) Heated tubs (800 "C) F Air/H, F - Heated tube 835 1192 1202 745 569 709 951 426 705 887 1251 3: 2. 3 2 a 5- 330 654 $ 10 1335 3 2 c s vn U V Zn Zn Zn Zn Zn Zn Zn Zn Zn Amines (indirect) Detergents (indirect) Various (9) 324.7 Water (CU) 318.4 Waters - River water, sediments, 213.9 Waters plants, fish - Lake waters - Waters, sediments - Water - Water - Waste waters - Wasie waters - Lake sediments - Cooling waters 324.7 Natural waters 240.7 (CU) (CO) - Waters 0.01-6 pg/rnl A Trace levels ng/rnl levels - Trace levels - - - From 20 pg/l (octadecylamine) 10 pg/I level 0.02-1 mg/l A A A A A A A A A A A A A L L L L L L L L L L L L L L Add EDTA, adjust to pH 7 and pass through Amberlite IRC-50(H) column.Wash with H,O and elute U with 3M H,SO,. React with Cu/ neocuproine, extract with CHCI, and back-extract with HCI See Cd, ref. 624 None See Cu, ref. 940 See Cd, ref. 1195 See Cu, ref. 1309 Extract long-chain primary amines as amino-Cr complex into nitrobenzene (A) Anionic detergents-add tris( o-phenanthroline) copper ( I I ) sulphate + NaCl and extract with MlBK (pH 2) NH, cobaltothiocyanate + NaCI and extract with C,H, (pH 7.3) (€3) Nonionic detergents-add Adsorb trace metal impurities on iminodiacetic acid ethyl cellulose and extract with acid, to obtain 10- to 20-fold concentration for Cd, Co, Cu, Fe Ha.Mn. Ni. Pb. Zn F Air/C,H, 573 2 Graphite furnace 2 (HGA-70) z ?? k b Graphite furnace 519 '8, (HGA-74) ;j* F - 408 $ Graphite furnace 487 Graphite furnace 621 F - 624 Graphite furnace 885 Graphite furnace 940 F - 1192 F - 1195 F - 1309 F - 059 - t: (FLA-100) (HGA-72) Graphite furnace 12 (Varian model 63) F Air/C,H, 40Table 4.5B WATERS, SEWAGE AND EFFLUENTS-continued Eieinent X/nm Matrix Concentration Tech.Ana’yle form Sampie treatment Aiomization Ref. L L L - L L L L - L L - L Various - (9) Underground waters hg/l levels A Complex impurity elements with DOC F - and oxine, extract with MlBK and n-amylacetate and evaporate mixed organic extracts to 10 ml (from initial H,O sample of 400 mi) Elements: Co, Ni, Fe, Cu, Zn, Cd, Pb, Bi, Cr elec:ronics to improve precision, Fccuracy and speed of analysis Description of high salt content sQlution P ICP in sewage sludge (0.99 g/100 ml) nebulizer.Results given lor 10 elements solubilized with HNOJHCIO, Review of methods I - Acidify with HNO, to pH < 1.5 and store i n Nalgene linear polyethylene or Pyrex glass containers. For Zn, only Teflon should be used.(Study of loss of trace metals on Sorage) - P ICP Automated FAAS system F - Application of microprocessor F - Graphite furnace (HGA-2000) - (Sb, As, Ba, Cd, Pb, Se. Ag, Te) Graphite furnace 75 A Various - Effluents 139 166 Various - Sewage sludge (10) Minor and trace levefs E Various - Waters Various - Natural waters (11) 186 196 - A Various - Various - Various - ( 8 ) Various - Various - (7) Various - ( 8 ) Various - Water Waste wafers Waters Water Water effluents Drinking water Waters Snow E mg/l levels A Trace levels A - 201 208 249 Review - - Automated monitoring system for F - Cd, Cr, Pb, Cu, Fe, Mn and Zn Assessment of AAS and XRF methods F - for Cu, Mn, Zn, Co, Cr, Ni, Pb and Cd Review of techniques, including AAS - - and OES Method for Pb, Zn, Cd, Mn, Cu Graphite furnace 288 328 Trace levels A b 361 Trace levels A 376 Various - (5) Various - Trace levels A 41 1 Inter-laboratory comparison, using F, A - FAAS, OES, XRF and NAA 414 Sewage sludges - A, E Lh Various - Waters (7) Trace levels Various - Surface waters; wastes - (23) Various - Effluent waters Trace levels (9) Various - Water (16) Trace levels Various - Environmental samples - Various - Drinking waters Trace levels (8) Various Various Various Various (25) (30) (15) (6) Various Various Various Various (13) - Coal waste leechates Trace levels - Water Trace levels - Environmental samples - - Waters Trace levels - Waters Trace levels - Paper mill effluents Trace levels - Waters - Waters A E A A A A E, A E E A A, E A E E L Digest with HCI/HNO, and ex:ract F - with APDC/MIBK (Fe, Cu, Zn, Co, Ni, Cd, Pb) L Multi-element direct-reading system P ICP L Study of trace element levels extracted Graphite furnace from fly-zsh under v a r i o s condi:ior,s (As, Be.Cd, Cr, Cu, Mo, Se, V, Zn) 19 countries) system L International study (35 laboratories; F - L Automatic sampling/computer-controlled Graphite furnace L (A) Acidify and spray (Cu, Fe, Mn, F - Zn 1 Cold vapour (B) Concentrate ( x 10) by evaporation and use sampling boat (As, Pb, Cd 1 (C) Cold vapour (Hg) L Study of 6 different leaching solutions P ICP L - P ICP F - L, G - P MIP L Extract as 1,lO-phenan:hroline/ F - perchlorate complex into nitrobenzefie (method for Fe. Cu, Zn, Mn, Cd, Co) emission modes L Comparison of absorption and Graphite furnace L - Graphite furnace L - P ICP L Series of papers OR multi-element P ICP ICP-OES analysis of waters 465 3 k '5 cc 480 5 482 ta b 5 3 533 5. 2 595 623 656 657 759 82 1 849 850 a77 aao 882 883 881 - P w...d Table 4.5B WATERS, SEWAGE AND EFFLUENTS-corzfinued 2. Element X/nm Matrix Ref. A!omizaiion Concentration Tech. Ana'yte Sample lrealmeat form Various - (7) ~~ Sea-water Trace levels A L Various - (7) Various - (8) Various - Various - Various - Water ng/ml levels E, A L Sea-water Trace levels A L A L Water Trace levels Water All levels E L A L Water - Sewage sludge Minor end A L trace levels Various - Sewage sludge (73) Minor and trace levels A, E L, S Various - Drinking waters Trace levels E L A, E L Sewage sludge - Sewage SlUdQe - Waters Trace levels A L A, E L (Zn. Cu. Cd. Co, Ni, Pb. Fe. Bi, Cr) A L Fresh and sea-waters Trace levels Extract with APDC + DDC into Freon T.F. Back-extract into 0.3M HNO, Comparison for ETA emission and absorption modes. (Al. Ba. Be, Cu. Mn, Mo, Ni) Extract wi!h APDC/MiBK and back-extract into HNO, U.S. Geological Survey standard water samples-general description Review of applications of plasma emission methods Review Of AAS + ASV methods Comparison of 5 treatments: (A) HNO, (B) HNO,/H,O, (C) HWHNO, (D) Dry-ash, 550 "C (E) R.f. ashing Dry-ash at 420 "C. dissolve in HCI/ HNO, and add La solution. (Various elements). Overall procedure includes several other techniques, p.g., OES, MS. NAA Review F Air/C,H, 836 Graphite furnace Graphi!e furnace 911 (HGA-2100) (HGA-2100) Graphite furnace 915 F - 937 (CRA-63) P ICP or 938 d.c. plasma F - 939 F Air/C,H, 1071 Graphite furnace (HGA-2000) F, A - 1072 b E. Y 2 * .. 1078 <' P ICP Comparison of ashing procedures Comparison of methods. including AAS, OES, NAA and ASV Extract with DDC and/or B-hydroxy- quinoline into MlBK or n-amyl ace?ate. Concentrate extract by evaporation Comparison of FAAS, NAA and XRF F - 1328 2Various - Drinking waters ng/ml levels A L Concentra'e Ag, Cd, Co, Cr, Cu, Fe, Graphite furnace 1348 2 (9) Mn, Ni, Pb by extraction wiih APDC/MIBK Various - Sea-waters (9) Various - Aquatic sediments - (10) Various - Natural waters Various - Natural waters A L Concentrate Cd, Co, Cr, Cu, Fe, Mn, Graphi!e furnace 1359 $ ;a "J A L Comparison of extraction methods: F Air/C,H, 1389 % Ni, Pb and Zn by extraction with APDC/M I BK 1360 ( A ) 4M HNO, + 0.7M HCI, at 70-90 " C (C) 1.OM NH,OH.HCI in 25% CH,COOH r? -.. (B) 0.5M HCI 9 z at 70-90 "C (D) 0.05M EDTA at pH 4.8 E L - P ICP E L - P ICP 1326 1427

ISSN:0306-1353    

DOI:10.1039/AA9780800124

出版商:RSC    

年代:1978

数据来源: RSC

摘要:

146 Analytical Atomic Spectroscopy 4.6 SOILS, PLANTS AND FERTILIZERS 4.6.1 Introduction The information that can be obtained solely from the elemental analysis of soils, soil extracts and plant tissues by analytical atomic spectroscopy is of rather limited value as far as understanding the complex mechanisms of plant growth is concerned. As West (764) has pointed out, although the results of routine elemental analysis are invaluable for soil fertility assessment and related purposes, non-atomic spectrometric techniques now have perhaps a more vital role to play because of their importance in speciation studies.Thus the past year has largely been a further period of consolidation, with minor improvements to established procedures of atomic spectroscopy. One area which has however attracted substantial attention is that of sample preparation techniques. There has also been a slow but steady increase in the acceptance of much-improved commercially available ETA systems for those trace elements for which the improved detectability attainable may be deemed essential. 4.6.2 Sample Preparation The most time-consuming stage in the analysis of soils or plants by the majority of atomic spectroscopic techniques i s undoubtedly that of sample preparation.Moauro et al. (210) pointed out that the primary advantage of NAA over AAS for plant tissue analysis lies in the fact that sample dissolution i s unnecessary, Some attempts have been made to find new dissolution techniques that are faster and/or safer. Existing procedures have been critically compared.Scott and Thomas (922) compared three dissolution techniques for soils, Although all three gave reproducible results, they found that a Na,CO, fusion procedure gave lower results for Cd, Cu and Pb (particularly for soils with a high organic matter content) than two acid digestion techniques. One of these, sequential digestion with HF and HClO,, appears to be distinctly dangerous because of the possibility of being left with unattacked organic matter and concentrated HClO,.The other, based on HNO, /H,SO, /MClO, sounds more useful, particularly if the pump and air-bleed fume removal system described are used. Yamasaki (921) compared fusion of soils with 10 : 1 Na,CO, : H,BO, with sequential digestion with HNO,/HClO, and HF/HClO,. He found both to be apparently satisfactory for standard rock samples, but his study did not include any of the more volatile heavy trace metals.Ritter et al. (1092) compared five sample preparation techniques for soils and sewage sludges prior to the AAS determination of Cd, Cu, Ni, Pb and Zn. These included ignition at 550 "C and HCI extraction, HNO3/HC1O, digestion, extraction by shaking with 6M HNO, for 6 h, HCl/HNO, extraction, and ignition at 550 "C following by HCl/HF digestion.No losses from dry ashing were observed, but spattering and contamination problems were encountered in wet ashing procedures. The preliminary results of another comparison of wet and dry ashing procedures, but for marine plant samples, have also been reported (1583). Significant losses of Pb were observed, even at 350 "C.Wahdat and Shamsipoor (491) have described a novel procedure for the determination of Pb in plants which would avoid such losses. The dried group plant material was heated in a silica boat at 280 "C in 0, for 20 min, and then for 10 min at 450 "C. The boat was then heated at 1000 "C in a stream of H,, and the metallic Pb sub- limed to the capillary end of the tube, where it was dissolved in a few drops of 40% HNO, for determination by AAS.It is of interest to note that the results were higher than those obtained by wet oxidation. Two groups have suggested dissolution of ashed plant samples in methanolic hydro- chloric acid rather than conventional aqueous acid as a method of enhancing the sensitivity of FAAS determinations.Hall and Parli (645) used 1 ml of concentrated HC1 diluted toChapter 4: Applications 1 47 100ml with methanol for Co, Cu and Zn determinations by FAAS. Boline and Schrenk (382) utilizcd a 2 : 3 solution of M HCl/methanol for Cu and Fc and obtained a 2-fold improvement in sensitivity. For some trace elements however, a mere 2-fold improvement in detectability would be insufficient to avoid the need for a concentration step. Moreover, the danger of incomplcte dissolution of trace elements such as Co from the ash residue must be borne in mind.Hoenig and Vanderstappen (1469) studied such losses in the determination of Cd, Cu, Mn, Pb and Zn in grasses. They concludcd that wet oxida- tion with HNO,/H,SO,/H,O, is the preferred technique because it is faster when the time-consuming steps required to affect complete residue dissolution are taken into account.Van Eenbergen and Bruninx (1385) studied the losses of 28 trace elements from certified orchard leaves using acid digestion bombs for sample decomposition. A mixture of HNO,/HClO, was used to destroy organic matter and HF/HClO, to remove siliceous matter. Losses were observed only for Ge and Mo and for elements such as Hf, La, Sc and Ta, which may be precipitated by either acid treatment.Concentration techniques are often useful for the trace analysis of plants, soils and soil extracts. Horvath et al. (700) concentrated Cu, Co, Fe (after reduction to Fe(I1) with ascorbic acid), Mn, Ni and Zn from ammonium acetate extracts of soils using iminodiacetic acid/cellulose on a cotton-wool support.The heavy metals were absorbed, and thus separated from the matrix and large excesses of the alkali and alkaline-earth elements, before being leached off with a small volume of M HC1 for analysis. There has been continued use of and interest in solvent extraction, both as a concentra- tion technique and as a method for overcoming interferences. Fudagawa and Kawase (540) found that the technique was useful for the determination of plant Ni by AAS using ETA; selective volatilization and background correction techniques were still necessary.Little and Kerridge (388) extracted Mo from soil saturation extracts as the thiocyanate complex prior to determination using ETA. An extraction ratio of 10 could be used because of the small sample requirements of ETA.Horak (444) determined Co and Mo directly in solutions of soil and plant samples using a graphite-furnace atomizer with deutcrium background correction. Solvent extraction-FAAS was used as a referee method for Mo in this study. The indirect determination of P via the determination of Mo in cxtracted phospho- molybdate by AAS i s a well known technique, which has now been applicd to corn samples (802).Schmidt and Diet1 (1236) observed considerable losses of Pb when attcmpts were made to store MIBK extracts of Pb as its A P E complex, and therefore recommended back extraction of the element with HNO,, which may also serve as a further concentra- tion step. Pedersen et al. (713 have used APDCIxylene for the extraction of Co and Ni and DDCIxylene for the extraction of Cd, Cu and Pb from EDTA extracts of soils and sewage sludges prior to their determination using ETA.The EDTA did not appear to effect the extraction efficiency. 4.6.3 Atomic Absorption Spectrometry Molecular absorption is not usually a problem in the analysis of soils, plants and related materials by FAAS. Simmons (9 lo), however, showed that non-specific background absorp- tion by Ca species from Ca in plant material could cause a systematic positive error in the determination of Cu by FAAS.The effect was minimizcd in a fuel lean flame and at a low total gas flow. It could be overcome by employing continuum source background correc- tion. No such effect was apparently observed by Lanning and Schrenk (443) in a comparison of FAAS and the official AOAC method for determining Cu in plant tissues.Campbell andTable 4.6 SOILS, PLANTS AND FERTILIZERS Element X/nm Matrix Concentration Tech* Sample treatment Atomization Ref. form L L L L L L L L L L L L L B Plants E - (See Agazzi; Anal. Absrr., 1968, 15, 2521). Extract B with 2,2,4-trimethyl- pentane-l,3-diol Digest with HNOJHCIO,, add L i solution and dilute Ash, extract with HCI and add LaCI, Extract soils with acetic acid and plant materials with HCI.Extract ( ~ 2 ) with dithizone/CHCI,, buffered with purified NH, citrate at pH 9 (Simultaneous 2-channel AFS (Cd) and AAS (Pb) system) (A) Fuse with Na,CO, and dissolve melt in HCi (B) Extract with HF, followed by HCIO, (C) Extract with HNO,/H,SO,/HCIO, (Add LaCI, to an.alysis solution) Wash, dry at 100 " C , ash at 500 "C and digest with 2M HCI Comparison with NAA results F Air/H, 373 1167 1109 221 922 248 444 645 89 89 248 382 443 B 249.8 Plants 2.5 ,ug/g level E P D.c.arc plasma Graphite furnace F - Ca - Cd - (wide- band system) Plants Plants; soil extracts E F Cd Soils 0-1 pg/ml (in extrac?) A F Air/C,H, From < 1 i a / g to 1% 0.06-4.64 pg/e (plants) (soils) 6.97-14.2 pg/g - F Air/C,H, Graphite furnace c o - c o - Plant leaves (genus Haurnaniastrurn ) Plants, soils, forage Dry-ash and dissolve in solution of 1 m l conc.HCI in methanol Dry at 70 "C, digest 0.5 g sample in 20 ml HNO, and dilute to 100 ml See Cr, ref. 89 See Co, ref. 248 F Air/C,H, F - F - F Air/C,H, F Air/C,H, F Air/C,H, co - Plants - Cr Roadside soils c u - c u - Roadside soils Plant leaves (genus Hniirnaniastrum ) c u 324.7 Plants c u - Plants Wet- or dry-ash and prepare solution in HCI : methanol (2:3) Comparison of FAAS method with official AOAC colorimetric method From 2 i a / g (dry sample)c u - Plants c u 324.7 Plants (barley, kale) c u - Soils Fe 248.3 Plants Fe - Pine trees Hg 253.7 Plants Mo - Soils - From 16 pg/g - - Trace levels Mo Ni P Pb Pb Pb - Plants, soils, forage - Plants - Corn (Mo) - Plants - Roadside soils 217.0 Plants; soil extracts 283.3 0.19-3.34 pg/g (plants) 0.58-5.73 pg/g (soils) 1.2 PS/S (orchard leaves) 5.1 pg/g (tea plants) - A A A A A A A A A A A A A L L L L L G L L L L L L L See Co, ref. 645 F Air/C,H, Digest with HNO,/HCIO, evaporate F Air/C,H, to dryness and redissolve.(Study of Ca inrerference) See Cd, ref. 922 F - See Cu, ref. 382 F Air/C,H, Tree-ring analysis F - Digest with HNO,/CrO, Cold vapogr (A) For total Mo, digest with HF/HCIO,, Graphite furnace (B) For extracts, either ( i ) express from F saturated sampie or ( i i ) extract with acid NH, oxalate. redissolve in HCI and dilute. (CRA-63) N,0/C,H2 For Mo > lpg/ml, use flame method, with addition of 1000 pg/ml La.For Mo < 1 pg/ml, extract with KCNS/ SnCI, into MlBK and use flameless method (See also Co, ref. 444). Results for Graphite furnace Mo compared with solvent extraction/ flame AAS results. Digest with HNOJHCIO, Graphite furnace Digest with HCI/HNO,, add NH, F - molybdate and extract with butyl acetate. Determine Mo i n extract Combust in 0,, reduce Pb oxides to Pb F - by high-temperature H, treatment and collect sublimed Pb on cooled surface.Dissolve in HNO, for analysis See Cr, ref. 89 See Cd, ref. 221 645 91 0 922 382 1235 493 388 444 540 802 68 826-3790 pg/g - P - 89 Graphite furnace 221 eTable 4.6 SOILS, PLANTS AND FERTILIZERS-continued c 8 Element X/nm Matrix Concentration Tech. Ana'yte Sample treatment Atomisation Ref.form Pb - Plants 1.8-6.3 ILg/g Pb Pb Pb Pb Pb S (SO,) 283.3 Soils - Soils - Plants - Pine trees From 0.5 ng/ml ( i n extract) - Soils and sediments From 0.1 pg/ml (in extract) 553.5 Fertilizers (Ba) Sr - Soils and vegetation 200 pg/g level (soils) 20-350 pg/g (vegetation) Zn - Roadside soils 104453 pg/g Zn - Plants - Biuret - Fert i I izers - (indirect) (Cu) Various - Natural vegetation - (15) (55 species) Various - Cabbage plants - (6) A L A L A L A L A L A L A L A L A L A L A L E S A, E L Dry, grind, combust i n 0, at 280 "C F Air/C,H, 491 and ash at 450 "C.Heat i n H, to sublime metallic Pb (1000 "C) and dissolve condensate i n HNO, Decompose with HF/HNO,, evaporate Graphite furnace 816 and dissolve i n HNO,. Alternatively, decompose with HF/HCI, evaporate, dissolve i n HCI and buffer with 1% ascorbic acid See Cd, ref. 922 F - 922 - F - 1219 Tree-ring analysis F - 1235 Extract sample solution with APDC/ F - 1236 MlBK and back-extract with HNO, Dissolve i n conc. HCI, evaporate F N,O/C,H, 895 almost to dryness, re-dissolve in 2M HCI, filter and dilute. Precipitate S as BaSO,, dissolve in NH,OH/EDTA and add K as ionization buffer Fuse soils with LiBO,.Digest Graphite furnace 49 vegetation samples with HNOJHCIO, (Comparison of AAS and NAA) See Cr, ref. 89 F - 89 See Co, ref. 645 F Air/C,H, 645 See Woodis et al.; Anal. Abstr., 1976, F Air/C,H, 377 31, 3G6 (Comparison with AOAC method 2072) in cratered electrode Dry, grind and extract with 1N HCI F Air/C,H, 46 (Hydro-cillture study of effect of Be, Sr + Mg.Ca, Na, K) Wash, dry at 70 "C, grind and excite S - 45 N,O/C,H2 a -* P 2 -.Various - Wheat Minor (K, Mg, Ca) A, E L (A) Pressure digestion F - ( 8 ) and trace (Fe, Mn. (B) Dry-ash and redissolve Zn, Na, Cu) levels Various - Plant leaves - A L Comparison of NAA and FAAS results F - 210 5 Various - Plant ash (12) Various - Soil extracts Various - Soil extracts ( 6 ) Various - Soils Various Various Various (7) (7) - Botanical samples - Soils - Soils for determination of Fe, Mn, K, Cu, Zn, Ca b 5., From 1 d g E S Mix ash with AI,O, + CaCO, + A - 365 (most elements) s internal standard.(Elements: Pb, Sn, -. Zn, Cu, Cd, Ag, Bi, Ga, Ge, Sb, TI, B) K,CO, (7:3:1), with addition of In as 2 c? - E L Extract with NH, acetate solution P ICP Trace levels A L (A) React 10 g amino-ethyl cellulose F Air/C,H, with 19 g chloroacetic acid at 70- 80 "C.Dissolve in H,O, neutralize with Na2C0, and oven-dry. Convert to NH, form 1N NH, acetate solution, centrifuge, filter, add ascorbic acid and pour solution through cellulose (see A above) on cotton wool in funnel. Elute heavy metals with 1N HCI (Fe, Cu, Mn, Co, Ni, Zn) (6) Extract air-dried soil with Trace levels Trace levels Major levels A L Grind and shake (24 hours) with Graphite furnace 0.33M NaEDTA + 0.33M acetate (HGA-2100) buffer (pH 4.7).Filter and extract aliquot with DDC/xylene (Cu, Pb, Cd). Extract second aliquot with APDC/xylene (Co) and, if necessary, repeat at pH < 4.25 (Ni) A L Comparison of methods, including AAS Graphite furnace F - A, E L, S Review of methods A,F - A L Digest with HNOJHCIO, followed F - by HF/HCI04 or, alternatively, fuse (1:4) with N~CO,/H,BO, (1O:l). Method covers Na, K, Mg, Ca, AI, Fe, Mn 662 700 71 7 737 764 921Trblc 4.6 SOILS, PLANT'S AND F E .R T I L T z E R s - ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ c \ 8 Element X/nm Matrix Concentration Tech. Analbte Sample treatment Atomisat ion Ref. form Various - Soils, sludges Various (Cd, Pb, A ( 5 ) Ni, Cu, Zn) Various - Soils Various - Pine trees Various - Tea leaves (21 1 Various - Orchard leaves Trace levels (28) Various - Agricultural samples - Various - Grasses ( 5 ) A A A, E - E A L L L L - L L Prepare sieved and dried (110 'C) F Air/C,H, sample and treat by one of the fo I I ow i ng : (A) Ignite at 550 "C, digest with 3N HCI, filter and dilute (B) Digest with HNOJHCIO, evaporate io dryness, redissolve in 6N HCI (C) Extract by shaking with 6N HNO, (D) Digest with HCI/HNO, (E) Ignite at 550 "C, treat with HF/HCI, evaporate t o dryness and redissolve in HCI Review Digest with HNO,, add HCIO, and dilute as necessary (See also Fe, Pb, ref. 1235) Study of tea leaves as biological standard material Study of element losses in acid- digestion bomb sample treatment - Comparison of 6 treatments. for determination of Cd, Cu, Mn, Pb, Zn d - F Air/C,H, F - - - P ICP F - 1092 1 1 1 1 1383 1384 1385 1421 1469 'I 2 2 2. 5 2. $ h 3 rQ 2 0 4 +-.Chapter 4: Applications 153 Tioh (895) found that it was necessary to employ a N20/C2H2 flame to overcome Ca interference in the determination of Ba by FAAS, when carrying out indirect determinations of fertilizer sulphate.The sulphate was precipitated as the Ba salt and the latter dissolved in aqueous NH,/EDTA prior to AAS determination of the Ba. A few other papers worthy of specific mention have been published. Gladney et al. (49) compared epithermal NAA, thermal NAA and AAS using ETA for the determination of Sr in soils and plants. Although epithermal NAA was recommended at very low Sr con- centrations, AAS appeared to be generally satisfactory.Thermal NAA appeared to give a systematic positive error. Lerner et af. (816) found serious matrix interferences in the determination of Pb using ETA in the presence of excess of chloride. A 1% ascorbic acid buffer was necessary to remove the effect in a HC1 matrix. Daniel (493) used a digestion mixture of 1.12% CrO, in concentrated HNO, for the determination of Hg in plants by cold-vapour AAS.It was shown that methylmercury chloride was completely retained and decomposed and thus included in the procedure. 4.6.4 Atomic Fluorescence Spectrometry AFS remains only rarely used in soil and plant analysis. Ure et al. (221) have however published an interesting paper in which Cd and Pb were determined simultaneously in acid extracts of soils and plant ash using ETA, the Cd by AFS and the Pb by AAS.For the Cd determination a vapour discharge lamp was used as source, and the fluorescence monitored with a solar-blind photomultiplier. The elements in the soil extracts were con- centrated by double extraction with dithizone in CHC1,. 4.6.5 Atomic Emiss’ion Spectrometry Dahlquist and Knoll (662) have published the results of an investigation of the use of an inductively coupled plasma for simultaneous multi-element analysis of plants and soil extracts. Data were acquired and processed by computer. They concluded that matrix effects could be rendered insignificant by careful matching of matrices, and that spectral and nebulization interferences could be readily overcome, The applicability of the ICP to agricultural samples has also been investigated by Hem (1421). Melton et al. (1167) have reported that the determination of B in HNO,/HC10, digests of plant materials by d.c. arc plasma OES compared favourably with the same determination by AAS. Li was added to prevent interference from other alkali metals. Parle and Fleming (365) used mixtures of plant ash, A1,0,, CaCO, and K,CO, for the spectrographic determination of B and heavy metals in plants, with In as an internal standard. They obtained a precision of better than 10% for most elements. Pickett and Franklin (373) have developed a filter flame photometer for the determination of B in plants by measurement of the BO, emission intensity from an air/H, flame. The B was extracted as its chelate complex with 2,2,4-trimethylpentane-1,3-diol. Intensity measurements were made at a maximum and an adjacent minimum in the molecular emission spectrum to overcome the need for a separate background reading.

ISSN:0306-1353    

DOI:10.1039/AA9780800146

出版商:RSC    

年代:1978

数据来源: RSC