摘要:

Applications 97 4.2 METALS The number of papers describing the application of the ICP continues to increase and many systems are in routine use. Analysis of solutions using ETA for AAS measurements is now treated as a standard technique for many determinations. ETA using solid samples is the subject of an increasing number of publications, but most of these are coming from a few groups of workers.Large numbers of papers continue to appear on the applications of FAAS and arc and spark emission confirming the usefulness of these techniques in metallurgical analysis, but few significant advances in methodology are apparent in these areas. There has been renewed interest in atomic fluorescence, although the number of papers is still relatively small. 4.2.1 Iron and Steels 4.2.1.1 Atomic Emission Methods.Tanaka et cd. (646) have studied the best conditions for the ZCP analysis of steels, They reported that detection limits for many elements were better than AAS. Wunsch (625) determined W in steels and alloys from 0.02-80% of composition with an ICP. Factors such as acid concentration were found to have a negligible effect on results. Matrix interference effects were reported in the ICP analysis of steel (2019, but these were minimized by adjustment of the observation height and carrier gas flow-rate.Good results were noted for major concentrations of Ni and Cr in stainless steel and also for traces of As, Ce, La and Ta. Beaty et al. (525) used spark sampling of steel to produce a metal vapour, which was carried by Ar to an ICP.Linear responses were found for Cr, Cu, Mn, Mo, Ni, Si, Ti and V. Butterworth (800) has reviewed the performance of the glow discharge lamp in the analysis of highly alloyed steel. Correction had to be made for the different sputtering rate of each sample. It was stated that for best results the length of exposure should be deter- mined by monitoring the current flowing through the lamp. 4.2.1.2 Atomic Absorption Methods. L’Vov and Pelievea (1839) have reported the deter- mination of Ce in steel using ETA. This i s one of the few credible reports of direct AAS measurement of Ce. The addition of La and use of Ta-lined graphite furnace allowed concentrations of 0.05-0,23% t o be determined. A number of different techniques continues to be reported for the direct analysis of solids by ETA.Aziz-Alrahman and Headridge have applied their induction furnace to the determination of Ag (311) and Sb (1757) in steel. Detection limits of 0.005 pg g-1 for Ag and 0.2 pg g-1 for Sb were obtained using 1-20 mg samples. Calibration graphs were also given (1757) for Cd, Se, Sn, Te, Tl and Zn. Frech and Lundberg (244, 1119) studied the distribution of Pb and Sb in steels using solid samples.The elements were found to be “fairly evenly” distributed. The same authors (245, 11 12) also used a cup furnace for solid samples and compared the introduction of sample to the cup at room temperature, followed by a conventional heating programme with introduction to a furnace maintained at 1800 O C . Isothermal atomization was found to improve both precision and accuracy. In a further paper (1679, the authors reported the use of an autosampler for the determination of various elements in steel by solid sampling ETA.Backman and Karlsson (1882) measured Ag, Bi, Pb, Sb and Zn in steels by ETA using 1-2Omg solid samples. Five to ten standard alloys were needed for calibration. Only one serious interference effect, the depression of Pb signal by 0.1% S, was reported, A graphite rod system has also been used for solid sampling work (924). Background correction was necessary for the determination of Pb and Zn in steel, and the deposit remaining after atomization was found to reduce the life of thc rod.The work on the use of graphite cups to introduce solid samples into a graphite tube98 A nalyticai Atomic Spectroscopy furnaec reported previously (AXAAS, 1978, 8, Ref. 129) has now been published (Spectro- chim. Actn, 1980, 35B, 3). Khavesov et al. (1890) determined P in steel solutions using Zr-treated graphite tubes. This eliminated the need to add La compounds. The sensitivity did not vary from tube to tube and maximal signal value was obtained after 2 or 3 firings.Vanadium in steel was deterrnincd (340) after dissolution of the steel in HCI. The recommended concentration for analysis was 2-20 ng in a 20 pl aliquot of solution. 4.2.1.3 Atomic Fluorescence Methods. The determination of C, P and S in steel by AFS in sputtered vapours was described by Gough and Sullivan (1003). Human and Butler (811) determined the same elements using a glow discharge emission source with an atomic fluorescenee detector. Detection limits of 0.01% for C, 0.004% for P and 0.002°/0 for S were reported. 4.2.2 Non-ferrous Metals and Alloys 4.2.2./ A toniic Emission Methods. A quantitative spectrographic method for the determina- tion of twenty-eight impurities in refined ruthenium and cadmium has been reported (1083). Germanium metal powder was added as an alloying agent to effect the instantaneous formation of a quasi-alloy system within the sample electrode.Kirkbright et al. (851) used an ICP with discrete sample introduction from a graphite rod atomizer for determination of trace and minor elements in uranium. Good agreement was reported with independently assessed values. Ebdon et al. (873) studied the parameters affecting the performance of an ICP in metallurgical analysis.Methods of optimizing the conditions were illustrated with ~-csults for Al/Ti alloys. A d.c. plasma has been used (64) for the analysis of silver scrap. The method was claimed to be fast, routine and inexpensive, and gave results of similar accuracy and precision to classical methods. Churella (65) used arsine generation with a d.c.plasma for the determination of As in zinc. It was not stated how problems of losses during dissolution (see Section 4.2.2.2) were overcome. Trace amounts of A1 in magnesium were determined with a low-wattage MIP (641). The chelate resulting after extraction with TFA into chloroform was vaporized by heating, and the resulting vapour introduced into the plasma.A detection limit of 50 ppb was obtained. 4.2.2.2 Atomic Absorption Methods. Headridge and Thompson (491) determined Bi in nickel-base alloys by introduction of solid samples into their induction furnace. Good results were obtained at concentrations from 0.02-10 pg 8-1. Trace levels oE Pt in silver have been determined (1830) by placing 1-25mg particles of solid into a graphite tube furnace.The authors claimed that best reproducibility was obtained when droplets of HNO, were injected into the furnace to dissolve the sample before a conventional heating cycle, begin- ning with a drying stage. Pate1 ct al. (1489) determined Cd, Co and Cr i n uranium solution by ETA without preliminary separation. The furnace was enclosed in a stainless-steel / PVC chamber to contain the radioactivity. Trace rare earths in uranium were also determined by ETA (2020) but preliminary chemical separation was necessary.Garbett et al. (1027) have studied the determination of trace elements in sodium by ETA with a graphite rod; Cr, Fe and Ni were measured at concentrations up t o 50 mg kg-1. Milner et al. (513) have published a novel method for overcoming the problem of loss of hydride forming elements from zinc during dissolution before AAS analysis.Arsenic and Sb were detcrmined by dissolving zinc powder in HC1 in the hydride system reaction vessel. The resulting hydride vapour was carried directly to the atomizer for measurement.Applications 99 4.2.2.3 Atomic Fluorescence Methods. Epstein er al. (1851) used an ICP as a narrow line radiation source for flame AFS for the determination of Zn in unalloyed copper.Spectral interferences normally present in this determination by direct ICP analysis werc cliniinated. Non-dispersive AFS with a carbon filament atom reservoir was found (1486) to give excellent results for Cd in copper-base alloys. Nakahara et al. (167) used non-dispersive AFS to determine Bi in aluminium-base alloys with hydride generation. Good agreement with AAS and TCP results was obtained.- 0 0 Table 4.2 METALS Element X/nm Matrix Concentration Tech.Analyte Sample treatment Atomization Ref. Form Ag 328.1 Iron,steel Ag - Steels A1 Al AS 328.1 Heat-resisting alloys - Sb-Pb alloys 338.3 Steels 338.3 Fe- and Ni-base alloys 309.3 Iron, steel 396-1 High-purity magnesium - Steel - Steels - Zinc 0.05 -5 pg/g A From 0.05 pg/g A ng/g levels A - A Trace levels A 0.03-1 -2 pg/g A From 2 @/g A 1.3-3.7 p g / g E Trace levels E - A ng/g levels E S S L L S S L L S L L, G Heat solid sample (2-20 mg) t o 2270 "C in furnace.Calibrate system with varying weights of reference steel, e.g., NBS SRM 361 Direct atomization of solid samples (1-5 mg) using modified autosampler.Atomization temperatures : Ag 2400 "C, Bi 2400"C, Cd 1700 "C. Pb 1800 "C, Zn 2400 "C Dissolve 0.5 g of Ni- or Co-base alloy in HNO,/HF/H,O (1 : 1 : 1) and dilute to 50 ml. Take 20 I aliquots, dry at 80 "C. ash at 500 '(2 and atomize at 2400 "C See Au, ref. 1661 F Air/propane/ Use 1-5 mg samples directly Use 1-20 mg samples directly Dissolve in H,SO,, dry at 100 "C, ash at Dissolve in HCI/HNO,/H,O (1 : 1 : 2) P MIP and extract Al as TFA complex into CHCI,.Evaporate and volatilize by heating, passing vapour to MIP system Graphite furnace Graphite furnace (CRA-90) Graphite furnace butane Graphite furnace Graphite furnace Graphite furnace (GRA-90) (IL-455) 1200 "C and atomize at 2700 "C (HGA-2100) Application of Pulse Distribution s - Analysis technique Two-channel ratio method.See also F - Mg, ref. 1378 Hydride-evolution method, using NaBH, P D.c. arc as reducing agent plasma 31 1 980 1147 1661 1675 1682 341 c E 2 641 5 818 $. b 1378 3 t" 65 $As 193.7 Zinc 0-5 pg/g levels As 193-7 Shot-gun pellets As 193.7 High-purity copper As As As Au Au 193-7 Copper, flue dusts - High-purity copper - Lead metal and alloys - Silver 242-8 Sb/Pb alloys B - Low-alloy steels (Cd) B - Molybdenum metal Be 313.0 AI/Mg alloy Bi 223.1 Aluminium alloys From 0.2 &g/g Various levels Trace levels (from 0.17 ELg/g) Minor and trace levels pg/g levels - - Trace levels (below 0-2%) A A A A A A A A A E c From 0.1 ng F (absolute) L, G L L L L G L L 1 S S G A Hydride-evolution method.Weigh 1 g F - 513 ’cr sample directly into reaction vessel, add 5M HCI at 80 “C and sweep As.Sb hydrides to flame, with argon 3 %. 9 Dissolve in 5M HNO, and dilute to 4M F Air/C,H, 754 HNO, and 0.5-1% Pb (matrix). Results given for As, Bi, Cu, Sb ,in 16 types of pellet and 9 standard alloys Dissolve 0.5 g sample in 3.5 ml H,O + 5 mi conc. HNO, and dilute to 50 ml. Take 20 2700 “C for As, Sb, Se, Te Graphite furnace 1051 (HGA-2100) aliquots and atomize at Dissolve in HCI/HNO, and dilute.Add F N,0/C2H, 1053 HF also if Si content high Dissolve in HNO, Graphite furnace 1333 Hydride-generation method, using Heated SiO, cell 2032 NaBH, - Graphite furnace 248 Dissolve in HCI/HNO,. add tartaric acid F Air/propane/ 166 and dilute to volume (1 g sample to 100 ml). To 2 ml aliquot, add 30 ml HCI (1 : 3) and extract with “petroleum sulphides” solution in toluene.Wash organic phase with HCI and dilute (1 : 1) with ethanol butane Indirect method, based on formation and F - 442 extraction of (BF,),L3Cd complex, where L= o-phenanthroline Dissolve under reflux in HCI/HN0,/H,02, A 25 A 781 add NaOH and evaporate with addition of C powder (A) Use solid samples as cathodes Hollow-cathode 1604 (B) Use powder samples in duralumln source cathodes Prepare solutions in 1 .OM HCI, add F Air/H, 167 NaBH, and pass evolved BiH, to flame, for excitation with Bi EDL zTable 4.2 METALS-ccontirzuad z f., Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form Bi 223.1 Aluminium alloys and solders Bi Bi Bi Bi Bi Bi Bi Bi Bi Bi 306.8 Nickel alloys 230.1 Lead 223.1 Shot-gun pellets 223.1 Ag/Cu alloys - Steels - High-purity copper - Iron 223.1 Steels 306.8 Fe- and Ni-base alloys 223-1 Steels C - Steel C 426.7 Iron, steel C - Metals From 0.1 ,,&mi A (in extract) 0.02-1 0 @/g A clg/g levels A - A Trace levels A ng/g levels A Trace levels A Trace levels A 0-7 pg/g A Trace levels A Trace levels, F from 0.01% up to 4% E L S L L L s L, s 1.S s L S S G Prepare sample solution in medium of F Air/C2H2 0.2M HNO, or 0.5-1 -OM HCI or H,SO,. Extract Bi with dibenzyldithiocarbamate into MIBK None (1-30 mg sample weights) Induction-heated furnace Dissolve in HNO, (2 : 1) and pass F - through column of 15% bis (2-ethylhexyl) PO, on Ptoroplast 4. Elute Pb with 0-3M HNO, and extract Bi with 3M HNO, See As, ref. 754 F Air/qH, Dissolve in HNO,. Dry at 100 "C, ash at 215 "C, atomize at 2485 "C and burn-out at 2500 "C See Ag, ref. 980 See Se, ref. 983 Comparison of methods. See also See Ag, ref. 1675 See Ag, ref. 1682 Dissolve (0.2 g) in HCI/HNO,, add H2S0, and evaporate to fumes. Dissolve in H,O, add NH,I 4- H,SO, and dilute t o 10 ml. Extract ( x 2) with 5 ml MIBK, back-extract with 6M HNO,, evaporate to dryness and dissolve in 0 - 5 ml 1 -5M HNO, Description of glow discharge source + atomic fluorimeter detector lamp Method for C using non-vacuum wavelength.Not applicable to graphitic carbon - Sputtered vapour Graphite furnace Graphite furnace Graphite furnace Graphite furnace Graphite furnace Graphite furnace Graphite furnace (HGA-72) ( C RA-90) "Various", ref. 1623 F - Glow discharge s - 300 491 701 754 784 980 983 1623 1 675 1682 b 2066 Y 2 3 ? 811 ah 832 2 T 2 1003C Ca Cd Cd Cd Cd Cd Cd Cd Cd Ce c o CO c o Co 426-7 Welded seams 422.7 Metals and alloys - Cadmium plating extract 228-8 Copper - Steels - Copper-base alloy 228.8 Uranium 228.8 Steels - 228.8 Steels H ig h-p ur i ty a I um i ni um 567.0 Steel - Acid gold plating solutions - Ferro-manganese - Tungsten carbide-cobalt alloys 245-0 Copper alloys 246.4 252.0 From 0.03% E &g/g levels A From 0.4 pg/ml E 0.2-28 pg/Q A (in extract) From 0.01 pg/g A - F A Trace levels A From 23 ng/g A Trace levels A 0.05-0.23 yo A (Detection limit 5 ng) 55 @nl A (average, in eluate) - A Major levels A - E S S L S S L L S G L L L L S A 1625 2 s - ( 9- laser evaporation) z Results given for Ca in tantalum metal, ferro-tungsten alloy and electrolytic iron Extract Cd from 0.05M LiI medium into F Air/town gas MIBK. Filter organic phase for analysis Graphite furnace (HGA-70) D.c.arc nebulization system for sample F Air/C,H, introduction to flame See Ag, ref. 980 Graphite furnace (CRA-90) Dissolve 0.2 g sample in HCI/HNO, (3 : 1) and dilute t o 100 ml.(Non-dispersive AFS system) Graphite furnace Dissolve in HNO,. Match standards for Graphite furnace U content (CRA-63) See Ag, ref. 1675 Graphite furnace Separate Cd by volatilization Graphite furnace See Bi, ref. 2066 Graphite furnace ( H G A-72) Use furnace lined with Ta foil, vaporize sample from W wire and add excess La solution. Atomize at 2700 "C, in argon Add 20 rnl 1M HCI t o 25 mi sample and pass through Amberlite IRA-900 anion-exchange column.Wash with H,O and determine Co in eluate. (Method for uncornplexed Ca2-F) Graphite furnace (HGA-76) F - Dissolve in HNO, (1 : l ) , dilute, filter F Air/C,H, and dilute t o volume. (Comparison of FAAS and ETA-AAS results) Graphite furnace - F - Homogeneity study s - 647 $. 0 323 @ 489 980 1486 7489 1675 1880 2066 1839 399 1148 1253 1479 c 09 Table 4.2 METALS-continued Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form c o Cr cr cr Cr Cr Cr c u cu c u c u c u cu Fe Ga Hg In 240.7 Uranium - Stainless steel 357.9 Low-alloy steel - Metallic sodium 425.4 Uranium 357.9 Low-alloy steels - High-Cr steels - 324.8 - - 324.7 324.7 - 294.4 Alloys Shot-gun pellets Aluminium Ferro-m ang anese Lead alloys Low-alloy steels Metallic sodium Nickel alloys - Zinc amalgam 303-9 Nickel alloys 1-30 pg/g u p t o 20% 0.1-3 * 0% 1 4 % A E A A A A A E A A A A A A A E A L S, G L L L L/S L L L L L c L/S L L L L See Cd, ref. 1489 Graphite furnace 1489 ( C RA-63) Application of spark source solid P ICP 74 sampling device, t o prepare argon-carried aerosol Dissolve 0.1 g in 20 ml conc.HCI + F Air/C,H, 314 few drops HNO,. Dilute to 100 ml. For analysis, take 25 ml aliquot, add NH,OH, HCI and dilute to 100 ml Convert to NaCl solution Graphite furnace 1027 (fuel rich) See Cd, ref. 1489 Graphite furnace 1489 (CRA-63) Prepare sample suspension by spark-in- F N,0/C,H2 1728 water technique (pH 2.5) Study of operating conditions F N,O/C,H, 1873 See Cd, ref. 323 F Air/town gas 323 See As, ref. 754 F Air/C,H, 754 Application of argon-stabilized d.c. arc A D.c. arc 981 atomizer t o replace normal flame See Co, ref. 1148 F Air/C,H, 1148 Dissolve in HNO, (1 : 1) and dilute. F Air/C,H, 1175 5' Method tested for Cu and Sb See Cr, ref. 1728 F Air/C,H, 1728 5 See Cr, ref. 1027 Graphite furnace 1027 ;j. Dissolve in HF/HNO, t o form 1 YO Graphite furnace 979 solution.Dilute as necessary See Cd, ref. 323 F Air/town gas 323 5 (lean) (+argon, C,H,) '1, 2 Graphite furnace 2 (CRA-63) See Ga, ref. 979 Graphite furnace 979 8 (CRA-63) 0 2Mn 279.5 Cast iron 0 - 05-0-19~/0 A L Cast iron A L High-purity magnesium - A L Steels 51rg level A L (absolute) Mn Na Ni Ni Ni NI Ni Ni Ni P 279.5 - Low-alloy steels 0.91% level A L/S Various levels E, A L Tellurium, selenium, lead alloys, tungstic acid, slags Stainless steel u p to 20% E S, G Alloys 0.04-70% E S.G 227.0 239.5 232.0 213.6 214.9 253.6 255.3 Metallic sodium Trace levels A L A L Ferro-manganese - (UP t o 50 f i s h ) A L High-alloy steels - Copper alloys - E S Low-alloy steels 0*6-3,6.% A L/S Iron and copper alloys - E c Digest with HNOJHCIO,, evaporate to dryness, redissolve in 50% HCI, boil, dilute and filter.Wash precipitate with hot H,O, and dilute filtrate t o volume after addition of SrCI, as interference suppressant Two-channel AAS procedure. Dissolve in F acid, dilute and measure Mg/Fe ratio, for comparison with reference ratios. No weighing or accurate dilution is required Dissolve metal in dehydrated phenol and F dissolve separated MgO in 2M HCI, for Mg determination To sample solution aliquot (up to 10pg Mn) add 0.4% solution of 4-phenyl-3- thiosemicarbazone of biacetyl monoxine in DMF 4- NH, buffer solution (pH 10).Extract Mn by shaking with 1% solution of tetrabutyl ammonium bromide in MlBK See Cr, ref. 1728 P For AES method, add 101% butanol. F (Comparison of 2 AES and 1 AAS methods) See Cr, ref. 74 P Spark-generated aerosol system, applied P to various standard alloys F F ~~ ~ Air/C,H, - Air/C,H, Air/C,H, Air/C,H, - I CP I CP See 13, ref. 1027 Graphite furnace See Co, ref. 1148 F Air/C,H, Two-channel ratio method. See also F - Mg, ref. 1378: See Co, ref. 1479 s - Graphite furnace See Cr. ref. 1728 P Air/C,H, Nebulize solution in argon flow and pass A - to stabilized arc device - b 404 'tr 3 2 g. 1378 1599 1968 1624 1728 1108 74 1 92 1027 1148 1378 1479 1728 708 c.s Table 4.2 METALS- continued Elemenl X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form P P P P Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Iron, steel Steel Metals Steel Ferrous alloys Metallurgical samples High-purity silver Iron, steel Copper Ag/Cu alloys Steels Steels and nickel alloys Steels, ferro-alloys, nickel alloys Zinc Ferro-manganese From 5 pg/g Trace levels, from 0.004% - From 0.05 pg/g (50 sample) ccg/g levels and above Trace levels, From 50 pg/g 0.2-60 pg/g From o.oo3% 2-200 pg/g Trace levels From 0.1 pg/g Trace levels (0.2-60 pg absolute) Trace levels Minor and trace levels A F F A A A A A A A A A A A A L S G L L S L L S L S S s, L L L Dissolve in HNO,/HCIO, and extract P F N,0/C2H2 as phosphorovanadomolybdic acid into MIBK.Measure V in organic extract See C, ref. 811 - Sputtered vapour Atomize at 2600 "C, using Zr-coated Graphite furnace graphite tubes Dissolve in acid and determine Pb by F Air/C,H, FAAS ( > 1 D Icg/g) or ETA-AAS Study of solid sample technique, on sample weights of 1-5 mg Separate Pb from matrix by fixation of Ag F - on Ni ferrocyanide ion-exchanger. Results compared with those of photon activation method Glow discharge lamp Graphite furnace Graphite furnace (< t O p € l / g ) (CRA-90) - F - See Cd, ref. 489 F Air/C2H, Graphite furnace See BI, ref. 784 See Ag, ref. 980 Graphite furnace Take 1-5 mg sample (0-2-60 g/g Pb) Graphite furnace Homogeneity study, by dissolution of Graphite furnace (2-100 mg).Results given for Pb, Sb To sample solution containing up to F Air/C,H, 100 g Pb add 0.05M Na,S,O,, adjust to pH t w i t h citric acid/NH,OH and extract with Capriquat into MIBK See Co, ref. 1148 F Air/C,H, ( C RA-90) and atomize directly at 1800 '% (CRA-90) small individual solid fragments (HGA-74) Graphite furnace 724 81 1 1003 1890 120 244 245 328 428 489 784 980 b % s 3 1112 2. 0 1119 2 1126 ?' kl B 5 a 2 1148Pb 28303 Fe- and Ni-base alloys 0-15 pg/g A S 363.9 Pb - Fe, Ni, Cr alloys Trace levels A L Pb 283.3 Steels Trace levels A L - Pd - Pd - Pt Pt Pt - - - Rh Ru - S - - S Copper Uranium Copper Silver Silver Uranium Uranium Steel Metals 1-1 (Yo pB/Q A, E 1, S Trace levels E S 1-100 p g / g A, E L, S pg/g levels A A 10 pg/g level Trace levels E Trace levels E Trace levels, F from 0.002% F - Sb 217.6 Zinc 1 - 6 pg/g level A Sb 217-6 Metals, alloys - A Sb 231 - 2 Sn/Sb alloys 10-120 pg/ml A ( i n extract) Sb 231.2 Shot-gun pellets - A Sb 217.6 Ag/Cu alloys Trace levels A L S S S S G L, G L 1 L L See Ag, ref. 1682 Graphite furnace Dissolve i n HCI/HNO,, or electrolytically Graphite furnace i n HNO, See Bi, ref. 2066 Graphite furnace (HGA-72) Inter-laboratory comparison of 13 F,A - different techniques (OES, AAS, XRF, NAA, MS, etc.) for determination of Pd and Pt Dissolve in 5M HNO, and extract with A - TBP/hexane. Evaporate organic phase with graphite powder f 5% CuF, as carrier See Pd, ref. 19 F,A - - Graphite furnace Place 1-25 mg sample in furn'ace, add Graphite furnace 50 HNO, (1 : 1) and heat to 80 "C.(HGA-72) Repeat with HNO, and then with HCI (10%) at 100 "C. Ash at 1650 "C, to remove AgCI, and atomize at 2600 "C See Pd, ref. 788 A - See Pd, ref. 78& A - See C, ref. 811 - Vapour sputtering Glow discharge lamp See As, ref. 513 F - Dissolve i n HCI/HNO,. evaporate t o dryness and redissolve in HCl/tartaric acid. Add NaNO, + urea and extract Sb with MIBK.Add thiourea as atomization interference suppressant Study of complexing agents for Sb, Sn F Air/C,H, determinations. Use of NH,F in HCI/HNO, medium recommended See As, ref. 754 F Air/C,H, See Bi, ref. 784 Mo micro-tube furnace Graphite furnace 1682 'ob 2066 3 1886 3 a 2. 19 788 19 248 1834 788 788 81 1 1003 513 622 626 754 784 E;c Table 4.2 METALS-continued 0 00 Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form Sb - Sb 206.8 Sb - Sb 231 * 1 Sb - Sb - Sb 259.8 Sb 231 -2 Sb Sb Se High-purity copper High-purity copper Mild steel Lead alloys Sb/Pb alloys High-purity copper Fe- and Ni-base alloys Pb/Sb alloys - Steels 217.6 Steels - High-purity copper Se 196.0 Se - Si 251.6 Si - High-purity copper Hig h-p uri ty copper Cast iron Aluminlum @g/g levels From 0.3 @/g Trace levels - O*1-30% Trace levels (from 0.32 ro/a) Major levels 4-1 76 pg/g 0.5-350 @/g Trace levels From 0.1 pg/g From 0.3 rg/g Trace levels (from 0.34 pa/s) 1.6-3.5% A A A A A A A A A A A A A E A L, s L s, L L L L S L S L L, s L c S L Graphite furnace See Se, ref. 983 See As, ref. 1051 Graphite furnace (HGA-2100) See Pb, ref. 1119 See Cu, ref. 1175 F Air/C,H, Dissolve in lO.% HNO, with addition of F - tartaric acid.Add I n as internal standard See As, ref. 1333 Graphite furnace Graphite furnace See Ag, ref. 1682 Dissolve in tartaric acid 4- HNO, and F - dilute to volume with additional HNO, and with addition of 100 g/ml In as internal standard. (Doubk-channel instrumentation) Direct method (1-20 mg samples) Graphite furnace Induct ion-heated furnace See Bi, ref. 2066 Graphite furnace (HGA-72) Dissolve in HNO,, dilute and add Fe( NO,), solution + cellulose filter aid. Add NH,OH to pH 3-5-4.0, boil and collect precipate on filter disc. Transfer 2 mm diam. punched disc t o furnace and atomize at 2250 "C. (Sb, Bi. Te can be determined by same method) Graphite furnace (CRA-63) or (HGA-74) See As, ref. 1051 Graphite furnace (HGA-2100) See As, ref. 1333 Graphite furnace Study of operating conditions in relation S - to sample metallographic effects See Cu, ref. 981 A D.c. arc 983 1051 1119 1175 1332 1333 1682 1745 1757 2066 983 s 7 B 1051 ; s. B 1333 2, z ? 981 04 ~~ ~~ Sn 286.3 Metals, alloys - Sn 224.6 Sn/Sb alloys 10-200 pg/ml (in extract) Sn 224.6 A1 alloys, brasses rg/g levels Te Te Te Te Te - Steels - High-purity copper 214.3 High-purity copper - High-purity copper 214.3 Copper TI - Aluminium Ti - Zinc alloys From 2 flg/g ng/g levels From 0 - 3 pcLs/g Trace levels (from 0.27 pg/g) 2-0-200 @/a - Trace levels TI 276.8 Co and Ni alloys Trace levels v 318.3 Steel 2-20 ng (absolute) v - High-purity uranium Trace levels (from 0.2 W 400.9 Steels, alloys 0~02-80% 207.9 W - Tungsten carbide-cobalt Major levels alloys A A A A A A A A A A A A A E A L L L L L, s L L L L L L L L L L t o improve performance " See Sb, ref. 626 F N,O/C,H, Prepare sample solution to contain 2-20 pg Sn, add Th (NO,), solution, adjust to pH 9 with NH,OH and filter. Dissolve precipitate in 2N HCI, dilute to 100 mi and take 10 Dissolve in HCI (1 : l)/HF/H,O, with F Air/C,H, heating, cool, add ascorbic acid (solid) + Kl/ascorbic acid/HCI reagent and dilute to volume. Extract with TOPO/MIBK and determine Te by comparison with aqueous standards Graphite furnace samples See Se, ref. 983 Graphite furnace See As, ref. 1051 Graphite furnace (HGA-2100) See As, ref. 1333 Graphite furnace Dissolve in HCI/HNO,, evaporate, treat with 6M HCI, evaporate and dissolve in 0-01M HCI.Add 1-7 ml conc. HCI to 1 mi aliquot and extract with 3 ml MlBK Mo microtube furnace See Cu, ref. 981 A D.c. arc Comparison of peroxide colorimetric Graphite furnace Dissolve in HF/H,S0,/H,02 Graphite furnace method (preferred) with ETA-AAS (HGA-2100) (HGA-2100) Dissolve in HCI. Atomize at 2650 "C Graphite furnace Separate V from U matrix by Dissolve in HCI/H,POJH,O and dilute P ICP to volume with H,O Graphite furnace anion-exchange treatment (HGA-2100) Discussion of interference effects in F - determination of W.ref. 1253 See also Co, A Dissolve in HCI or HCI/HNO,. Treat Graphite furnace 623 'cr furnace with NaWO, or ZrOCI, solution (HGA-72, HGA-76) 3 9 k 626 -=' 2 1042 782 983 1051 1333 1582 981 1396 2025 340 357 625 1253 -I Table 4.2 METALS-continued L 0 Element X/nm Matrix Concentration Sample treatment Atomization Ref.Tech. Analyte Form W - Zn 213.9 Zn - Zn 307.6 Zn 307-6 Zn 213.9 Zn 213.9 Zr - Various - Varlous c Various - Low-alloy steels - Copper 0.5-2.5 fig/g Steels From 10 @/g Steels Trace levels Fe- and Ni-base alloys 6-116 @/g Copper - Technical iron and I ferro-al loys Molybdenum met a I Metals, alloys and - intermediates Magnesium Trace levels Trace levels (below 0.2%) A L, S A S A S A S A S F L A L E S A, E L, S E S Silver scrap I E L High-purity cobalt and pg/g levels E S compounds Metals A l l levels E S, G See Cr, ref. 1728 See Cd, ref. 489 See Ag, ref. 980 See Ag, ref. 1675 See Ag, ref. 1682 F - F Air/C,H, Graphite furnace Graphite furnace Graphite furnace (CRA-90) See "Various", ref. 1851 F Dissolve in HCI and pass through Dowex F 1-X10 (chloride form) resin column. Analyse eluate for Fe. Determine (Zn 4- Fe) on unseparated solution See B, ref. 781 A Discussion of sampling techniques - Dissolve in HNO, (1 : l ) , with addition of NH,OH to prevent loss of B, and convert to MgO. Then : (A) Mix with 5% AgCl for determination (B) Mix with 50% AgCI, for B (C) Mix with 5% KCI or CsCI, for L i (D) Mix with graphite (1 : 1) for Al, Cr - P A of Cd, Co, Cu.Fe, Mn, Mo, Ni, Si Convert metal or compound to Co,O, and A mix with graphite powder. Prepare synthetic standards in Co,O,. Elements quoted : Ca, Cu, Cr, Fe, Mg, Mn, Ni, Si Application of solid-sampling device. P See also Cr, Ni, ref. 74 I - 25 A - - D.c. arc plasma 9 A d.c. I CP 1728 489 980 1675 1682 1851 1970 781 5 15 5 2.? % 64 ' 66 s. % ; 74 2 2 2 h4 Varioua (9) Various Various Various Various (131 Various (7) Varlous Various (9) Various Various Various ( 25) Various Various (12) Steel Minor and trace E. A S. G levels Silver and silver residues Minor and E Aluminium bronze Trace levels E trace levels Iron. steel - Metals, alloys - A E Electrolytic copper 0.1-20 p g / g E E Steels; Al alloys - Nickel Alloys Trace levels All levels A E Steel - - High-purity lead Trace levels A Steels Metals 0.032-O.66% E (various elements) E - S s, L L S S c L S - L L L Combined AAS/OES assembly, using laser vaporization of sample surface.Data given for Cr, Ni, Mn, Mo, Cu, Al, Ti, V, W Elements quoted : Au, Pd, Pt, Cu, Ni, S - Pb, Sn, Zn, Sb, Bi, Cd, Se, Te OES methods applied to the analysis of A,S - Al-bronze reference standards Review, with 12 refs., of field tests for A - identification and differentiation of metallic materials Melt samples in graphite crucible at A D.c.arc 1200 "C, transfer t o Pyrex tube under vacuum and use solidified specimen as one electrode, for determination of Ag, As, Sb, Bi, Se, Sn, Pb Study of high-temperature flames for F Various determination of : gases (A) Cu, Cr, Mn, Ni i n steel (B) Cu, Fe, Mn, Ni in Al alloys Dissolve in HNO, (2 g/lOO ml).Results quoted for Sb, As, Bi, Cd, Pb, Se, Ag, Te and TI Generate metal vapour by sparking solid P ICP sample in argon, and transport vapour directly to ICP. Results given for ferrous alloys ( 8 elements), Al alloys (9 elements) Description of high-precision standard - - samples for determination of 0, N, C and S in steel Dissolve i n 20% HNO,,evaporate almost F - t o dryness and extract with small aliquots of 65% HNO,.Evaporate total extract to 1-2 ml and use "pulse nebulization" funnel technique - P ICP Laser microprobe (LMA-10) Review, 66 refs. F - Graphite furnace (HGA-2100) Review P ICP A 128 'n s. 247 8 256 37 1 397 429 443 51 6 525 599 628 648 650 Ld Table 4.2 METALS- continued - w Element A/nm Matrlx Concentration Sample treatment Atomlrat ion Re?. Tech. Analyte Form Various - ( 6 ) (5) (5) Various - Various - Various - Various - (9) Various - Various - (6) Various - Various - ( 7 ) Steels Ferro-manganese Copper alloys Steels High-purity thallium Anti mony Steels High-alloy steels Steels: Ni-base alloys Steels, cast irons Titanium and alloys - A - A Minor and trace A levels Trace levels E Minor and trace E levels Various levels E Trace levels E (0*1-100 &25% E Minor and trace E levels L L L S L S S S S S S Method for separation and analysis of metal carbides from fast-cutting steels F Method for Cu, Pb, Co, Ni, Zn F (A) For Pb, dissolve 1 g in 10ml (1 : 1) F (B) For Fe, Mn, Ni, Zn, dissolve 1 g in HNO,, without heating 10 ml (1 : 1) HNO, + 5 ml HF i- 3 ml (1 : 1) H,SO,.Evaporate to fuming and dilute Results improved by pre-heating aerosol Procedure for remelting steel samples t o S produce discs for spectrographic analysis solution on Apiezon/petroleum ether- impregnated electrode. Elements : Pb, Mg, Cd, Zn, At, Cu, Ni, In Dissolve in HNO,, evaporate and ignite at 900 "C.Mix residue with graphite powder Evaporate small volume of sample A A c Air/C,H, Air/C,H, - A.c. arc D.c. arc Study of operating conditions and presentation of results for Si. Mn, Cr, Mo, Ni, At, Co, V, W Description of magnetically stabilized glow discharge source lamp Use 10 mg sample, in He atmosphere. Results given for Pb, Bi, Zn, Ag, Sb, Ca Glow discharge lamp (1200 V) Glow discharge Hollow cathode New multistage excitation source s - V.U.V.method, covering 0, N, At, V, Mo, S - Si, Zr, within wavelength range 200- 2300 A (20-230 nm). Use Ti 50.8 nm or Ti 149-8 nm as internal standard wavelengths 684 688 719 767 789 791 800 5 ij ", 801 $ 806 ,b 0 829 2. 835 2 2 T 2 04 Various - Steels, Ni alloys Various levels E S (77) Var i oua - High-purity tin Trace levels E S (10) Various - Uranium Various - Metals Various - Iron, steel Various - Metals, alloys Trace levels Trace levels Various - Steels, bronzes, Al alloys - Various - Ferro-alloys (20) Various levels Various - High-purity Sb and Te crg/g levels metal Various - Steels (6) pg/g levels Various - Fe- and Ni-base alloys - Various - Steel ( 5 ) O/O levels E E E A L L S L S S L G s E S Detailed comparison of performance of S - glow discharge lamp and spark unit, in Glow discharge analysis of complex alloys Dissolve tin conc.HNO,. evaporate to A 12 A d.c. dryness and ignite at 500 "C. Mix oxide with (C2H,),NI 4- KIO, and excite in graphite cavity electrode atomizer, dry and vaporize by electrical heating, in argon flow leading to ICP injection system Apply 20 sample t o graphite rod P ICP ( +heated graphite rod) Study of operating parameters P ICP Generate sample aerosol by spark P ICP Applications of Continuum Echelle F - volatilization of solid sample Wavelength Modulation system (CEWM- AAS).Examples include Zn. Pb, Mg, Cd in Ni alloys and Zn in Cu and Fe metals - Graphite furnace (A.3470) Fusion/graphite briquette procedure, S - using Pt/Au crucibles Method for Fe, Cu, Pb, Bi, As and Te in F Hydride-evolution method for As, Bi, Sb, Heated SiO, cell Se, Sn, Te Procedure for direct-reading analysis of S - ferrous- and nickel-based alloys on a single programme Study of counter-electrode (W, Ag) S - phenomena in determination of C, S, P, Si and Mn Investigation of procedures for handling S - small-diameter samples Mix with Ge metal powder, to form alloy within sample electrode and to accelerate i m p ur ity vol at i lizat ion (i- spark source) Air/C,H, Sb and for Fe, Cu, Ag, Pb and Se in Te NJH, A D.c.arc (Stallwood) A 836 2 851 873 874 91 6 924 947 962 984 1007 lo40 751 1083 + I Various - Steel - E S (15) (28) and iridium (various elements) Various - High-purity ruthenium 1-1000 pg/g E S wTable 4.2 METALS-ccoritinued Element X/nm Matrix Concentration Tech.Form Sample treatment Atomizatlon Rer. Various (7) Various Various Various ( 6 ) Various (13) Various (7) Various (18) Various Various (12) Various Various Various Aluminium Fine gold Gold alloys Steel Steels Aluminium Uranium and its compounds Hig h-purity materials Nickel alloys Standard ferrous alloys Steels Steels Minor and trace E S levels - YO levels E S E S pg/g levels A L Minor and trace E S levels Various levels A, E L, S Trace levels E S ng/g levels A, E L, S - A L E S - E S - - Convert to oxide and adhere t o flat-ended A A.c.arc graphite electrodes. Prepare mixed oxide siandards. in AI,O,, for B, Cu, Fe, Mg, Mn, Si and Ti Study of internal standardization Glow discharge source Combination method, including - gravimetry, titrimetry, spectrophotometry, polarography and OES Dissolve in HCI/HNO,, boil, dilute with 2M HCI and add ascorbic acid.For Ti, add cupferron and extract with MlBK + tri-octylammonium chloride. For Zn, Sn, Bi, Cu and Cd, extract with a mixed cupferron/M IBK/tri-octylammonium chloride reagent.I n both procedures, wash extract with HCl/ascorbic acid Application of luminescent discharge P spectrometry Preparation and verification of disc standards for Si, Fe, Cu, Mn, Mg, Zn, Ti Investigation of spectrochemical carriers A ( 1r$03, AgCI, NaF) Review of high-sensitivity techniques, - including FAAS, ETA-AAS, FAES Match matrix composition of standards to that of samples.Elements : AI, Cr, Cu, Ti, Mo, W, V, Fe, Nb, Ta, Mn, Cu Homogeneity study on standard reference S alloys, using 3 alternative excitation sources Investigation of sensor-lance sampling S system Discussion of secondary standards in the steel industry F F, A P - - N ,0/C2H2 (for Ti) Air/qH, (others) Argon plasma - - - Air/C,H, N,O/C,H, - - - 1107 1109 1111 1114 1120 1141 1143 1171 1236 1355 1379 1380a Various - Various - (8) Various - (7) Various - (15) Various - Various - (6) Various - Various - (17) Steels Steels Copper Steels Iron Rolled steel Aluminium, zinc High-purity Re and Ga; doped Si layers Various - Tin brcnze Various - (6) Various - Low-alloy steels (6) Capper Various - (5) Metals and alloys - A Trace levels A E E Trace levels A E E - - - Trace levels A, E - 0 * 01 -2 Yo up to 5% E E A - A L S S S L S S, G L S S L S Review Graphite furnace 1395 Sol i d-s am p I i ng technique .Res u Its Induction-heated 1445 presented for Sb, In, TI, Sn, Se, Te, furnace Cd, Zn Description of preparation of range of A - 1474 high-purity copper standards (Be, Bi, Ca, Cr, Mn, Ni, Sn) - Glow discharge 1509 Review of methods (114 refs.) F - 1623 Sampling procedure, with results for C, S - 1633 S, P.Si, Mn, Cr - P MIP 1657 source Graphite furnace ( +laser evaporation) (A) Re-Dissolve in HNO, and remove F - matrix by extraction (x2) with tri-N-octylamine/toluene. Use FES (HGA-74) for Li, Na, K and ETA-AAS for others (B) Ga-Dissolve in HCI/HNO,, take to dryness and redissolve in HCI. Remove Ga by extraction ( x 3 ) with Chlorex. Use FES for K, Na; FAAS for 10 elements and ETA-AAS for others (C) Si layers- Remove with HF/HNO, for determination of In, TI, As, Sb Study of sample-mass effects s - Preparation and performance of s - standards for analysis of foundry copper Dissolve in HCI/HF, oxidise with few F Air/%H2 drops HNO,, boil, add NH,CI buffer and dilute to volume. Determine Mo, Cu on this solution (0.1 g sample in 100 ml) and dilute further ( x lo), with addition of AICI,, to determine Cr, Ni, Co, Mn System based on time- and spatially- resolved AA measurements, using pulsed HCL sources Graphite furnace Laser 1671 1823 1825 1826 1850 c c.- Table 4.2 METALS-coritirtued - cn Element X/nm Matrix Concentration Sample treatment Atomization Ref. Tech. Analyte Form Various - (14) Various - (up to 17) Various - (9) Various - (8) Various - ( 5 ) V ar i ous - (Rare earths) Various - (23) Metals; aqueous solutions - F L Use of ICP as narrow-line radiation F - source for AFS acid solu?ions of irons, steels, Cu alloys and Al alloys Cd, Pb, Se, Ag, Te and TI P, Sn (NaDDC/MIBK) methods for Pb. Bi, Cu. Fe, Cu, Al alloys - E L Concentration-ratio method, applied to P ICP High-purity nickel Trace levels A L Dissolve in HNO,. Method for Sb, As, Bi, Graphite furnace Steel A l l levels E L Results given for As, B, Bi, Ta, Ce, La, P IC'P High-purity tin Trace levels A L Comparison of direct and extraction F - Zn, Ag U matrix. Treat atomizer with HF solution (CRA-63) of Ta to improve Sm results (2 : 1) carrier mixture Uranium 0 05-1 0 pg/m I A L Separate Dy, Er, Eu, Sm chemically from Graphite furnace Uranium Trace levels E S Convert to U,O, and add 6% Ga,O,/SrF, A 13 A d.c. 1851 1856 1869 201 5 201 9 2020 2024

ISSN:0306-1353    

DOI:10.1039/AA9790900097

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

Applications 117 4.3 REFRACTORIES AND METAL OXIDES, CERAMICS, SLAGS AND CEMENTS It is of interest to note that during the year there has been an increase in the number of papers describing emission techniques, Many of these involve plasma sources, such as the ICP, which has been widely acclaimed in geological work since its inception some years ago. It is perhaps surprising that this excitation technique has not hitherto received more atten- tion in the analysis of refractories and ceramics.In absorption studies, ETA techniques appear to be gaining in popularity, and in one paper (3439 a plasma source was coupled with an AA spcctrophotometer for the determination of elements that are difficult to atomize. Appropriate to both emission and absorption techniques wcre two papers by Crossley and Oliver, respectively, on dissolution of refractory materials; summzries of these wcre published in Proceedings of the Analytical Division of the Chemical Society (1 979, 16, 149 and 151).Many of the papers presented this year contain no fundamentally new features, how- ever, the authors have consolidated existing techniques by assessing interferences and by establishing optimal instrumental parameters.The first part of a comprehensive review of atomic spectroscopy methods for metallurgical materials has been published by Belcher (1891). This deals with non-metallic metallurgical raw materials and such products as carbonates, corrosion products, fluxcs, non-metallic inclusions, product oxides, oxide films, concentrates, refractoriss, slags and sulphide concentrates. 4.3.1 Refractories and Cements An unusual sintering technique was reported by Masin et al. (1217) who treated a 0.4g sample of silicate with 1 g of flux (1 + 5 mixture of K,C,O,.H,O and Na,CO,) at 750 "C for 10 min. The cooled melt was extracted with 1 + 1 HCl and analysed for Cu, Fe, Mn and Zn by AAS. Rigin and Simkin (2064) claimed that silicate materials can be dissolved 3 to 5 times more rapidly by a fusion technique than by acid decomposition. Their fusion mixture contained 1 part of Li,B,07 plus 4 parts of LiBO,; the melts were dissolved in 6M HNO,.Uchida et al. (1676) decomposed a variety of refractory silicates by acid dis- solution and analysed these by ICP-OES. CRMs were used to confirm that their procedure was satisfactory.In a modern adaptation of an old technique, Sacks and Clark (1356) determined selected metals in refractory powders by AES with exploding thin-film excitation. Micro samples deposited onto polypropylene strips were subjected to high voltage impulses in an Ar/O, atmosphzre. Detection limits of 10-10 to 10-12 g were obtained for 10 elements. Russian authors (1628) determined noble metals in silicates at the level of 0.01-0.2 ,ug g-1 by chlorine preconcentration.The powdered sample was heated in a tube at 850 "C, through which was passed a stream of chlorine for 15min. The volatile metal chlorides were collected and concentrated on the top of a flat-topped water-cooled graphite electrode; this was then burnt in a conventional a.c. arc spectrograph.Deane and Lees (1 183) reported serious interference by Ca in the determination of Na and K in Portland cements by conventional flame photometry. Their studies showed that molecular band emission from Ca interfered with the Ida emission at 589nm. The K emission was supprcssed by the presence of Ca. These effects could be overcome by chang- ing the addition of A1 from 850 mg 1-1, as specified in B.S. 4550, to 2000 mg 1-1. Thc authors recommended that the British Standards method be modified accordingly. Voinovitch et ol (922) have carried out a systematic study of inter-element interferences in AAS applied to cements and slags. Individual elements, binary and tcrnary systems were examined. In an AAS method described by Toshihisa et al. (334), trace elements in cements were analysed by direct atomization of the powdered sample in a C furnace, Precisions obtained118 Analytical Atomic Spectroscopy were Cr 3.2%, Cu 3.4%, Mn 3.7y0, and Pb 2.8y0, and the values were in fair agreement with those obtained by standard methods.Detailed procedures for the analysis of Portland cement by AAS have been worked out by Crow and Connolly (1988) for 12 major compo- nents and trace elements. 4.3.2 Metal Oxides Alumina-supported automotive catalysts have been analysed by a variety of methods. Minochkina et al. (696) fused the sample with a 12-fold excess of K2S207, the melt was dissolvcd in 3N HC1 and a portion was taken for the determination of Pb; Pd was extractcd with phenanthroline in CHC1, and both elcments were determined by AAS.Altsrnatively, the catalyst elcments were extracted from the base with aqua regia. Potter and Waldo (1560) preferrcd to extract Pt from the base by prolonged treatment with conc. H,SO, and HC1. They added Pd and Rh to compensate for inter-elcment effects, and analysed the solution for Pt by ETA. They claimed a precision of 2% at the 0.04% level. The use oE d.c. plasma OES was found by Kosenberger (1082) to eliminate the necd for lengthy chemical pretreatment in the determination of Pt in a catalyst.Matrix-matched standards were used. The analysis of rare-earth oxides was carried out by Friedmann er al. (1106) by using a d.c. arc enclosrd in an A r l o , atmosphere; the working concentration ranges were from 0.002-2% depending on the matrix and thz elements to be determined.Robert and Mallett (430) determined Eu in rare-earth oxides by AAS with a N,0/C2H2 flame and also by ETA-AAS. They used a method of standard additions for calibration and achieved a precision of 2-5% at the O.&% level for the flame method, and about 20y0 at a concentra- tion of 5 pg ml-1 for the ETA method. Polyanskii et al. (1 167) claimed a precision of better than 1% for the same determination.In their method an isotope dilution procedure was uszd; after conccntration the oxides were excited in a cooled hollow-cathode discharge. The 153Eu component of the Eu line at 576.5nm was measured to determine the Eu content of the sample. Refractory elements were determined in U,O, by Dalvi et al. (316) using carrier distillation OES with a d.c.arc. To 100 mg of sample, a mixture of NaF and AgCl (1 4-9) was added as a carrier together with Pd as internal standard. The authors claimed a precision of 8-1696 for Hf, Nb, Ta, Th and W with detection limits at tbe ppm level. Kolihova et al. (753) determined Cr, Cu, Fe and Mn in TiO, pigments by ETA-AAS in concentrations down to 0.5, 0.5, 0.3 and 0.1 pg g-1, respectively.Optimum conditions were giveE for attaining these levels. D.c. plasma emission spectrometry was used by Griffin and Savolainen (63) for the analysis of titanium dioxide; 18 impurity elements were examined. 4.3.3 Ceramics and Glasses A comprehensive review of the analysis of glass and ceramics by atomic spectroscopy has been carried out by Wise et aI. (1983). The determination of 67 elements that are major, minor and trace constituents in these matrices is critically discussed.The paper describes how OES, FES and AAS have been employed as complementary techniques for establishing the composition of these materials. A two-chamber graphite electrode was described by Semenova et al. (30) for the spectrographic analysis of trace impurities in silica by matrix sublimation.The lower chambcr was packed with a fluorinating agent, and the upper chamber (connected to the lower chamber by a narrow channel) was packed with the sample (50mg). The electrode was heated at temperatures up to 300 O C to volatilize the Si. It was shown that more thanApplications 119 90% of the impurities remained in the upper chamber. In the spectrographic method for the analysis of silica proposed by Karyakin et al.(1602) a d.c. arc in an Ar atmosphere was used. The sample was mixed with carbon powder and a carrier (10% of NaCl or NaF) in a wine-glass-shaped carbon anode and excited by a 20 A arc; with a NaF carrier Al, Fe, Mg and Ti were detected at levels of less than 1 pg g-l. Sobel and Hassell (119) determined As and Se in silica by atomic absorption spectro- metry after dissolution in NaOH followed by hydride generation using sodium borohydride.Direct ETA-AAS methods for the analysis of trace elements in a variety of materials including glasses, rocks, fly-ash and uranium oxide were studied by Siemer and Baldwin (531). The solid samples, mixed with graphite powder, were excitcd in seven different atomizers and optimum conditions established. It was concluded that, with the correct atomizer and procedure, rapid and accurate determinations were possible for a n u n b x of volatile trace elements only simple matrix-free solutions being used for calibration.A rapid AAS method for the analysis of small glass fragments (250-500 pg) for forensic studies (see ARAAS, 1978, 8, 111) has now been published (42).The determination of Fe, Mg and Mn was considered sufficient to characterize the glass. Samples were digest:d in a mixture of HF, HC1 and water by ultrasonic agitation at room temperature. Portions of 2COpI were injected into tapered 2ml sampling cups and aspirated into the flame; the mponse for each element was recorded on a chart. The authors claimed improvemznts in speed and accuracy over previously reported AAS methods, and the possibility of analysing hrge numbers of samples on a routine basis.In another paper, Catterick and Hickman (1 179) described the use of ICP-AES for a similar application. A rapid sample throughput (5min 40s per sample) was achieved for the determination of Al, Ba, Cr, Fe, Mg and Mn. Locke (876) has reported a comparison of the use of the ICP and the d.c.plasma for glass classification in forensic work. Interest in the analysis of uncient glasses and ceramics is illustrated by two papcrs on AAS (431, 432) and one on OES (840). In this work, the main objective is to obtain the maximum amount of information on the smallest quantity of snmplc. Lambxt and McLaughlin (431) were able to characterize both the matrix, and the minor elements that give the colours, in early Egyptian glass.They used both AAS and X-ray photoclectron spectroscopy. Asnarez and Bonilla (299) determined boron in glass by AAS after digzstion with alkali and extraction from the aqueous phase with 2-methylpentane-2.4-diol in MIBK. It was claimed that there is no interference from any of the matrix elements.Boron was also determined in glass by Burdo 2nd Snyder (1548) who used d.c. plasma OES. The samples were dissolved in HF at room temperature and the insoluble fluorides wcre filtered. Deter- minations could be made in the range 0.01-100% B,O, with a best precision of 0.8%.- Table 4.3 REFRACTORIES AND METAL OXIDES, CERAMICS, SLAGS, CEMENTS Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. - g Form As - Silica As - Glass Au 267.5 Silicates B B Ba Bi Ca Ca Ca Ca - Glass 249.7 Glass 249.8 I Glass and raw materials - Oxide varis?ors - Glass and raw materials - Uranium oxide - Alumina Pellets - Cement Trace levels 1 OU-500 pg (absoluie, i n extract) All levels 0.1-12% (as BaO) 0.2-5% (as Bi,O,) 0.05-7% (as CaO) From 1 From 0.01 O/O Major levels A A E A E A A A E A A G L S L L L L L S L L Dissolve in NaOH.Reduce with NaBH, to generate As, Se hydrides - F Heat powdered sample at 850 "C i n A stream of CI, and collect volatile chlorides on H,O-cooled graphite electrodes. Excite in arc, with Na-impregnated graphite counter-electrode (Au, Pd, Pt) Digest with alkali, neutralize, adjust to 1.8M H7SOd concentration and extract B with 2-methylpentan-2,4-diol/MlBK Dissolve in HF (cold), filter and dilute.(Interferences by Na, K, Li, Si, P discussed) - F P F F - Treat 0.2 g ground sample with H,SO, f (NHJ2S0,. Heat to fuming, cool, dissolve in H,O, add tartartic acid and dilute to 100 m l F A - For Ca, Li determinations, add 19% of mixed carrier (3 parts NaCI, 1 part Y203).For Na determination, add 4% Fuse with Na,CO,/H,BO,, dissolve and make alkaline with NaOH. Separate Ca by co-precipitation with SrCO, and Mg by precipitation as Mg(OH),. Dissolve in HCI for analysis In203 F Fuse 0.2 g with 1 g Li metaborate, F dissolve in 180 ml 5% HCI and dilute to 250 ml. (Study of errors in standard addition method) - - 10 A a.c. N,O/C,H, D.c. arc p lasma - Air/C,H, - - - Air/C,H, N,0/C,H2 119 1235 1628 299 1548 356 1867 356 1146 $ $ 2.EL 1156 b a" b 1643 2 0 2 2c o - ~~~~~~ A I,O,/S i0, catalysts - A co c o Cr Cr Cr Cr c u c u c u c u cu c u Eu Eu Oxide varistors Uranium oxide Ti0,-base materials Cement Metal oxide-on-silica catalysts Uranium oxide Ti0,-base materials Cement Silicates Silicates Metal oxide-on-si lica catalysts Uranium oxide Rare-earth oxides Rare-earth oxides 0.1-3.1% (as COO) A ng levels (absolute) A d A 4.1-17.1 ng (absolute) A - A ng levels (absolute) A - A 5.0-16.0ng (absolute) A Trace levels A A - - A ng levels (absolute) A A - E - L L S t S L S L S L L 1 S L S Comparison of various techniques, F - including AAS, for analysis of AI,O,/SiO, catalysts impregnated with Mo, Co, Ni oxides See Bi, ref. 1867 F Air/C,H, Direct method: 5 mg sample Graphite furnace Dissolve in HF Graphite furnace (HGA-70) Direct solid-sampling method Graphite furnace Digest with HCI/HNO,/HF i n pressure F N,0/C2H2 vessel at 120 "C. Cool, add 3 g H,BO, and dilute (250 ml for 0.15 g sample) See Co, ref. 1879 Graphite furnace See Cr, ref. 28 Graphite furnace (HGA-70) See Cr, ref. 334 (e.g., Ca) t o standard solutions Fuse with K,C20,.H,0/Na2C0, (1 : 5) F - at 750 "C, treat with HCI, evaporate and redissolve in HCI (1 : 1) See Cr, ref. 1499 F Air/C,H, Graphite furnace Add excess of a major element F - See Co, ref. 1879 Dissolve in HNO, and add KNO, to F N20/C,H, final solution Combined OES/isotope dilution method. Hollow cathode Mix sample with IslEu-enriched oxide, dissolve with HF/H,SO,, precipitate Ca + lanthanides as oxalates, heat to 500 "C and dissolve in HNO,/H,O,.Precipitate with NH,OH and convert to oxides by ignition. Excite oxides i n argon atmosphere in HCL, and measure 151Eu and 153Eu at 576.5 nm. Mix separate sample with '51Eu2O3, calculated from first indication of result, and repeat analysis Graphite furnace A 9&7 'cr 5 %. 1867 2 1879 28 334 1499 1879 28 334 796 1217 1499 1879 430 1167 c !2L Table 4 .? REFRACTORIES AND METAL OX1 DES, CERAMTCS, SLAGS, CEMENTS-continued t4 t-4 ELement h/nm Mairix Concentration Tech.Sample treatment Atomiza.ion Ref. Form F - Glass ( CaF band) YO levels E L - Fe - Ti0,-base materials - A L See Cr, ref. 28 A - 275 Graphite furnace 28 (HGA-70) Fe Fe In K - Silicates - Synthetic garnet - Thorium oxide - Cement Fe 248.3 Glass fragments 0.01 -0.19 c/o A L Digest with HF/HCI/H,O (1 : 2 : 9) F Air/C,H, 42 after preliminary cleaning with HNO,.Prepare standards for Fe, Mg, Mn in similar acid mixture. Aspirate 200 aliquots, by pulse-nebulization method A L See Cu, ref. 1217 F - 1217 A L Add LaCI, solution F - 1965 E S Mix sample with 5% AgCI+O.l% Ga,O, A D.c.arc 1629 E L Add Al (850-2000 pg/ml) to sample and F - 1183 standard solutions and Ca (650 pg/ml) to standards, t o overcome interference effects A D.c. arc 1629 La - Thorium oxide 10-500 pg/g E S See In, ref. 1629 L I 670-8 Lithium niobate 5 1 5 % (solid) A L Powder, mix with KHSO, i n Pt crucible F Air/C,H, 1054 synthetic crystals 2 M O pg/ml and fuse at 500 "C. Extract melt with N,O/C,H, (short-path) (in extract) H,SO,/H,O, L i - Uranium oxide From 1 @/a E S See Ca, ref. 1146 Mg 202.5 Glass fragments 0.054 * 1 '/o A L See Fe, ref. 42 Mg - Glass and raw materials 0.1-3% (as MgO) A L - Mg - Alumina pellets From 0.01% A L See Ca, ref. 1156 Mn - Ti0,-base materials A A L See Cr, ref. 28 Mn 279.5 Glass fragments 42-306 pg/g A L See Fe, ref. 42 A - 1146 F Air/C,H, 42 $ F - 356 F - 1156 Graphite furnace 28 F Air/C,H, 42 2.(HGA-70) i? Mn - Cement 6.0-25.9 ng (absolute) A S See Cr, ref. 334 Graphite furnace 334 h Mn - Silicates - A L See Cu, ref. 1217 F - 1217 ' Mn - Oxide varistors 0.05-2.2% (as MnO) A L See Bi, ref. 1867 F Air/C,H, 1867 2 Mn - Uranium oxide ng levels (absolute) A S See Co, ref. 1879 Graphite furnace 1879 0 2 2 0Mo Na Na Nb Ni N i N i N i Pb Pb Pb Pb Pb Pd Pd Pd Pd Pt Pt Sb - - - - - - 351 *5 - - - 283.3 283.3 - 342 * 1 244.8 244.8 324.2 265.9 265.9 - AI,0,/Si02 catalysts Uranium oxide Cement Thorium oxide Silicates AI,O,/SiO, catalysts Metal oxide-on-si lica catalysts Uranium oxide Cement Glazed cooking ware Alumina catalysts - A From 15 ng/g E - E 10-500 pg/g E Trace levels A - A - A ng levels (absolute) A 3.6-16.8 ng (absolute) A (in extract) - A pg/ml levels A Pd/A $0, cat a I ys t s 0.12-7 9% A Synthetic garnet 0.4-2.1'1'0 A Zirconium oxide catalysts 0*0(41-0~01 YO E A Alumina catalysts - Pd/AI,O, catalysts 0 * 04-0 * 79% A Silicates Trace levels E Alumina catalysts 0.01 -0 * 2% A Silicates Glass Trace levels E (from 0.2 + V g ) - A L s L S L L L S S L L L L S L L S L S L See Co, ref. 987 See Ca, ref. 1146 See K, ref. 1183 See In, ref. 1629 See Cu, ref. 796 See Co, ref. 987 See Cr, ref. 1499 See Co, ref. 1879 See Cr, ref. 334 F - A - F - A D.c. arc F - F - F Air/C,H, Extract with 4% acetic acid F Fuse with excess (xl(rx12) K,S,O, and dissolve melt i n HCI/HNO, or, alternatively, digest with HCI/HNO,, filter and wash with HCI Fuse with excess ( x 10-x 12) K,S,O,, extract with 3N HCI and dilute to volume with 3N HCI.Calibrate by method of standard additions P F Add LaCI, solution F Grind (<200 mesh) and mix (1 : 1) with A carbon powder containing 4% NaCI. Use Zr 343.8 nm internal standard See Pb, ref. 771 F See Pb, ref. 696. Prepare solution in 3N F HCI, as for Pb determination, and extract aliquot with 0.01M phenan;hroline in CHCI,.Measure Pd in extract. See Au, ref. 1628 A Graphite furnace Graphite furnace - Air/C,H, - - 18 A a.c. Air/C,H, - 10 A a.c. Digest with HCI/H'SO, and add Pd, Rh, to compensate for interelement effects See Au, ref. 1628 A 10 A a.c. Graphite furnace (HGA-2100) - F - 987 5 1746 1183 $. 1629 2 796 987 1499 1879 334 353 771 696 1965 747 771 696 1628 1580 1628 1235 w- h) P Table 4.3 REFRACTORIES lZND METAL OXIDES, CERAMICS, SLAGS, CEMENTS- continued Element X/nm Matrix Concentration Tech* Sample treatment Atomization Ref.Form Sb - Oxide varistors 0.24% (asSb,O,) A s e - Silica Trace levels A Si 251.6 Metal oxide-on-silica - A catalysts Thorium oxide Silicates Silicates Tungstic oxide; sodium tungstate Boron carbide Silica Various - Titanium dloxlde (18) Various - Glass Various - Silicates (10) (5) (6) ( 5 ) Various - Glass Various - Quartz Various - Uranium oxide 2-1 00 pg/s E Trace levels A - A Trace levels E Trace levels, E Trace levels E to 100 pg/g Trace levels E A l l levels A Major and minor levels A Major levels A Trace levels A pg/g levels E (of Hf, Nb, Ta, Th, W) L G L S L L S S S L L L L L S See Bi, ref. 1867 See As, ref. 119 F I See Cr, ref. 1499 F See In, ref. 1629 A See Cu, ref. 796 F See Cu, ref. 1217 F Separate impurities electrolytically with A graphite electrodes and remove surface deposit for analysis containing 5% AgCl or 1% Li7C07 Concentrate impurities by removal of matrix using fluoridizing agents, e.g., NH,F, PTFE, NH,F + NH,NO,. (Recoveries checked by radioactive isotope technique) Dissolve i n HF/HNO, (1 : 3) and dilute t o 4% total solids level Mix (1 : 1) with carbon powder A A P Dual-channel AAS (IL.751) F F - Air/C,H, 1867 119 N,O/C,H, 1499 - D.c.arc 1629 - 796 - 1217 12 A d.c. 25 21 A (d.c.) 29 or 7-9 A (a.c.) 30 - D.c. arc 63 plasma Fume with HF/H,SO, and determine Al, F Air/C,H, 271 cc Fe, Mn, K, Mg o'n dissolved residue Graphite furnace Elements quoted : Fe, Co, Ni, Mn, Cr.Cu Graphite furnace 273 2. Heat i n Pt at 850 "Cfor 1 h, add 10% of A 12 A D.c. 316 2 AgCI) containing 0.01 % Pd as internal standard and proceed by carrier-distillation method 0 carrier mixture (1 part NaF + 9 parts 2 2 r)Various - Various - (9) Various - Various - Various - Various - (14) Various - Various - (9) Various - Various - Various - (Rare earths) Soda-lime glass Glass Glass (Early Egyptian) Ancient ceramics Glasses, oxides, wastes Metal oxides Boron carbide Ilmenite; Ti0,-based pigments High-purity alumina Ancient glass beads Glass fragments High-purity quartz Cataiysts (ceramic, metal) Rare-earth oxides A l l levels A, E L A l l levels A Major and A minor levels A A A Trace levels E - - * pg/g levels A Trace levels E E - Various levels E E - 0.002-2 Yo E [various elements) L L L S L S L 6 S L S L S Dissolve in HF/H,BO,, in pressure vessel. F Elements quoted : Si, Al, Fe, Ca, Mg, K, Na, Ba Decompose with HF treatment or Na,CO, F - fusion Results given for Na, Ca, Mg, K, Al, Cu, F - Pb, Fe, Mn - Review of experimental conditions F - Graphite furnace - (CRA-63) Study of ICP/AAS system applied to P ICP analysis of refractory oxides Grind, moisten with C,H,OH, dry at A 18 A d.c. 100 "C and then : (A) For Fe, Si, Ca, Al, Mg excite 10 mg portion in cratered electrode (18 A) ( 8 ) For Cu, Ti, Cr, Ni, Sn, Pb, Zn mix 50 mg portion with la% Li,CO, and excite i n cratered electrode (15 A) or 15 A d.c. A procedure for Na, K also given See also ref. 29 - (See ref. 28) Graphite furnace Mix with graphite powder + carrier, t o A D.c.arc determine Ca, Fe, Mg, Pb, Sn, Si, Mn, Cu and Ti Mix with graphite powder + Li,CO,. A - Add Ga, Pd as internal standards Comparison of ICP and d.c. plasma OES P ICP and methods for forensic analysis of glass fragments. (Al, Fe, Mg, Mn, Rb, Sr, Ti, V) Dissolve in HF, volatilize SiF, and collect A impurities on graphite. Add carrier t o mixed residue Method for determination of Pt group P D.c.plasma metals Mix oxide sample (e.g., La,O,, CeO,, A 17 A d.c. Nd,O,) with graphite powder (1 : 1) (HGA-70) D.c. plasma - (in Ar/O,) 332 2 z =t Q 376 2 431 432 531 343 744 753 833 840 876 991 1082 1106 r-. h) inc Table 4.3 REFRACTORIES AND METAL, OXIDES, CERAMICS, SLAGS, CEMENTS- continued h, Q\ Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref.Various - Glass fragments Various levels E L Wash fragment (2U0-5OOpg) successively P ICP 1179 Form with HNO,, H,O and acetone, dry, weigh and digest with HF/HCI (1 : 2) in (5) Various Various Various Various Various ( 6 ) (10) (5) (9) Various Various (67) (12) Various (8) Various Various Various - Slags - Refractory fragments - Silica - Silicates - Refractories, slags, oxides, etc. - Glass and ceramics - Portland cement - Ceramics - Heteropoly complexes - Silicates - Coloured glasses pg/g levels Major and minor levels All levels - Major levels Major levels - ultrasonic bath. Dilute with H,O and add Cr as internal standard. Elements : Al, Ba, Fe, Mg, Mn. (See also ref. 876) (7 : 3). Elements : Al, Ca, Fe, Mg, Mn, Si A L Dissolve under pressure in HCI/HF F Air/C,H, 1280 E S Exploding thin-film excitation method S - 1356 N,0/C,H2 E S Mix (1 : 1) with graphite powder and/or A 20 A d.c. 1602 E L Dissolve in HF/HCI in PTFE pressure P ICP 1676 A, E L, S Review (248 refs.) - - 1891 NaCI, NaF. Elements : Mg, Al, Fe, Mn, Ti vessel, in cold. Add H,BO, A, E L, S Review - - 1983 L Dissolve in HCI or fuse with LBO, F Air/C,H, 1988 A N ,O/C,H, E L - P ICP 2030 5 6 E L Application to analysis of complex ions, P ICP 2052 $ e.g., molybdates, tungstates. Examples g A L Fuse with 1 part Li,B,0,+4 parts LiBO, F - 2064 2 given : Mo, W, As, P and dissolve in 6M HNO, 3 2 2 3 E L - P ICP 2070 6' 2 % 0

ISSN:0306-1353    

DOI:10.1039/AA9790900117

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

Applications 127 4.4 MINERALS The continuing demand for high speed multi-element analysis in geochemical research has promoted, during recent years, the development of emission spectroscopy. In particular, the introduction of plasma sources such as the ICP has led to the improvements in sensi- tivity and precision necessary for a full analysis. Simultaneous determinations of major and minor constitutents and trace elements on a large scale are now commonplace (6, 203, 728, 1710) and these are frequently automated.Absorption methods are more commonly used for single-element determinations, although schemes for full analysis are published from time to time, For the trace elements, methods of sequential extraction of groups of elements have been proposed (324) and this is an approach that may gain in popularity.There is still considerable interest in the determination of Au and other precious metals at low levels, both by emission and absorption methods. The technique of “slurry atomization”, mentioned in ARAAS, 1979, 8, Ref. 50, for the analysis of coal, has now been extended by the authors (215, 530, 546, 1361, 1694; see also Section 3.1.4) for the analysis of major, minor and trace constitutents.The procedure may also be applicable to other geochemical materials. 4.4.1 Atomic Emission Methods - Arc and Flame Sources In the multi-element analyses reported by Golightly (6), the spectral information collected by a scanning microphotometer was analysed with a minicomputer and automatic matrix correction was applied.Pinault (978) has derived statistical methods to be applied to major and minor constituents to correct inter-element effects. Filo and Matherny (750) claimed however to have eliminated matrix effects by determining optimum conditions of analysis using statistical and computational methods. Doerffel and Tagle (778) determined Cu, Ga, In, Mn and Ni in the range 0-60pgg-l in ore samples by nebulizing solutions into a stabilized mc.These metals were extracted from the ore by treatment with HF/HN03/H,S04, KCl and isopropanol were added and the solutions nebulized in Ar. To determine Ge, the sample was decomposed by fusion, neutralized and evaporated to dryness. Germanium was extracted from the dry residue with CCl,, back extracted in H,O and nebulized after the addition of isopropanol.Govindaraju and Ouaida (1149) used a similar method for the determination of Al, Fe, Mn and Ti in ilmenites. Gold has been determined spectrographically in complex ores (32) after electrolytic preconcentration. After decomposition in aqua regia the Au was deposited, from HCl, on the flat top of a graphite rod electrode. The electrode was then excited in a d.c.arc at 12A. In another paper (131, enrichment of the noble metals was obtained by the combined use of two older methods, namely the cathode layer effect and the use of a spectroscopic buffer of BaCO,/NaCl. An enhancement of 2 to 5 times in sensitivity was claimed, giving detec- tion limits of 10, 30, 15, 4, 10, 5 and 20 ng for Au, Ir, Os, Pd, Pt, Rh and Ru, respectively.Lokamina et al. (36) determined Ru and 0s in magnetic pyrite ores by chemical precon- centration. The ore (1 g) was fused with 5 g of Na,O, and the cooled melt was extracted with H,O, K,Cr,O, and H,S04 were added to the solution and the mixture was boiled; RuO, and OsO,, which distilled off, were collected in traps containing 2-mercaptobenzoxazole in aqueous DMF. The combined extracts were evaporated on graphite powder and analysed spectrographically. Danilova et al.(770) carried out a preconcentration of noble metals with a chelating resin. Solutions treated with the resin were boiled for 2 h and graphite powder was added. The resin and graphite were filtered on paper, which was then ashed at 500 “C. The concentrates were then examined spectrographically; p g amounts of Au, Ir, Os, Pd, Pt and Rh were determined in copper/nickel ores and in flotation tailings.128 Analytical A tomic Spectroscopy An unusual spectrographic application was the determination of fluoride in geological materials reported by Sugimae and Skogerboe (1540), in which the fluoride was first converted to CaF, by treatment with Ca(OH),.In order to achieve complete volatilization of the CaF, in a d.c.arc, a “popwp” electrode was used. An arc was struck between a pair of large electrodes, the lower one of which was tubular. The sample electrode was then raised into the arc through the tube at a steady rate until the sample was completely consumed. The determination of Na by frame atomic emission spectrometry was used to good effect by Duty et al.(565) for the characterization of coal and lignite residues. Acid functional groups ( a g . , sulphonic acid, carboxylic acids and phenol) absorb Na ions in a manner that is markedly dependent on pH and concentration; NaHCO,, and NaOH were used to discriminate between the acidic groups, and the absorbed Na ions were rcmoved with HC1 and then determined by FAES. Accurate determination of K in rocks and minerals was achieved by Bairova and Shanin (3’39) with FAES using an air/CH4 flame and measuring the intensity of the K line at 769.9nm.The dark current was minimized by cooling the photomultiplier to -25 “C and interferences were suppressed by adding MgC1, to the test solution. A method for the determination of extremely low Concentrations of Cs in silicate rocks by FAES was reported by Miksovsky and Rubeska (676).Their method was based on separation preconcentration of Cs by coprecipitation with ammonium tungstophosphate. The sample was dissolved after sintering with Na,CO, and NaNO,, HNO, and NH,NO, solutions were added followed by 50% tungstophosphoric acid. The precipitate was filtered and dissolved in alkali borate solution; Cs was determined by F&S down to 0.5,ugg-1. 4.4.2 Atomic Wsdion Methods - Plasma Sources Bankston et al. (58, 1710) have evaluated a d.c. plasma source for the rapid analysis of silicate rocks. Samples (200 mg) were fused with lithium metaborate, and the melts dissolved in KNO, (1 +24) containing CsCl at a concentration of 0.4% nz/V. The solutions were analysed for major, minor and trace constituents.Solutions obtained from CRMs prepared in the same way as the samples were used for calibration. It was claimed that the Cs and Li minimized matrix effects due to ionization interferences. The results obtained were in good agreement with certificate values. A similar plasma emission technique for simul- taneous multi-element analysis was developed by Boucetta and Fritsche (868).In this method the samples were dissolved in an HF medium. Arsenic has been determined in sediments (1471) by chloride formation and d.c. plasma spectrometry. Samples were heated in an induction furnace in a HCl/Ar atmosphere. The AsCl, evolved was trapped and then swept into a d.c. plasma. The addition of CaSO, enhanced the signals and suppressed the interference from organic matter. From the many papers written on inductively coupled plasma analysis during the year, it is apparent that the composition of the matrix and the salt content of the analytical solutions both affect the emission to a significant degree. It is interesting to see how the various authors overcame these effects. Everett (87 1) determined the platinum group metals by a precipitation technique followed by leaching with aqua regia.Golightly and Simon (8671, in their analysis of igneous rocks, prepared acid solutions in which the total salt concentrations were kept as low as possible. Maessen and Kroonen (231) found it necessary to separate major constituents such as Fe and Si in order to determine the trace elements. In a German paper (20289, powdered samples were briquetted in the form of electrode rods with Cu powder and excited in a flow chamber with an intermittent d.c.arc against a graphite counter electrode. The vapour produced was swept out with Ar and transportedApplications 129 into an ICP torch. Since no fusion or dissolution stage was necessary, i.e., no dilution, the total sensitivity of the method was claimed to be higher than by other methods.In two papers by Broekaert et al. (1476, 1654) on the analysis of rare-carth minerals, matrix effects were studied. It was shown that the interference from Na,B,O, used as a flux could be minimized by adjustment of the carrier gas flow. It became evident in the second series of experiments that high concentrations of Na,B,O, lowered the excitation temperature and also caused quenching of metastable Ar, which, according to the authors, contributes largely to the observed matrix effect.An extraction technique first proposed for AAS work (see ARAAS, 1978, 8, 113) has now been developed for use with an ICP (1742). Aliquat 336 (tricaprylmethylammonium chloride) was used for the selective extraction of Ag, Au, Bi, Cd, Cu, Pb and Zn from solutions of geological materials. In addition to the freedom from matrix effects, consider- able concentration of the elements was claimed. 4.4.3 Atomic Absorption and Fluorescence Methods In the early days of the technique, it was suggested that AAS would take the chemistry out of analysis. From a review of the papers published during the year it i s evident that a great deal of chemistry is coming into analysis by AAS.With the increasing demand for trace analysis, more use i s being made of solvent extraction for the separation and concen- tration of the analyte. Procedures based on ion exchange, coprecipitation and chromate graphy are also finding renewed popularity. The role of AAS in modern geochemical laboratories was reviewed by Walsh (4) and by Hutchison (762) and its relationship to other techniques such as XRF and ICP analysis was discussed.The development of methods for Hg in geochemical materials was reviewed by Nicholson (2). Hannaker and Hughes (324) proposed a complete solvent extraction scheme for geo- chemical trace analysis. Groups of elements were extracted and concentrated in a stepwise fashion; chloro-complexes, DDC and Shydroquinoline chelates were used with MIBK and butyl acetate as solvents.Practical detection limits using FAAS were generally better than 0.2 yg 6-1 for some 14 elements. Solvent extraction is widely used for the determination of precious metals in geological samples. Two authors (1838, 1982) used MIBK to extract Au from acid solution, but others preferred extraction with what was described as “petroleum sulphides in toluene” for the concentration of Au and Pt; detection limits were respectively, 0.0005 and 0.001 pgml-1.Gil’bert et al. (2065) carried out a preconcentration of Pt group metals by extraction with alkyl-aniline in toluene. A detection limit as low as 5X 10-12 g was achieved for Au; for Ir, Pd, Pt, Rh and Ru the limits were of the order of 5X 10-10 g.Several papers have been published describing solvent extraction methods used in the determination of Ag in ores. The various extraction systems included triphenylphosphine and MIBK (1 159, 1-(2 pyridylazo)-2-naphtholate and MIBK (3 I), KI and isoamyl alcohol, DDC and butyl acetate (6861, and diphenyl dithiourea and butyl acetate (I 575).Matrix effects in rock samples were overcome by Aruscavage and Campbell (1592) by extraction of Pb with DDC in xylene, followed by back-extraction into HNO, medium. The determination was carried out on 13 standard rock samples and a recovery of at least 98% was claimed. Kane (1570) determined nanogram amounts of Bi in rock by ETA-AAS Samples of 100 mg were decomposed in HF/HC10, and the Bi extracted as the iodide complex with MIBK.After back-extraction with EDTA in the presence of hydroxylammonium chloride, Bi was atomized in a graphite furnace. In the ion exchange method used by Kuroda and Seki (1899) for the determination of Co, a cation exchange column containing Bio-Rad AG 50W X-8 resin was used to separate130 A n a1 y tical A tom ic Spectroscopy Co, A1 and alkaline earths from polyvalent ions including Fe3+.The Co was then selectively stripped by elution with 1M HCl in 84% acetone/H,O solution. Eames and Matousek (1201) determined Ag in silicate rocks by grinding the solid sample with graphite to 5pm particle size and atomizing in a carbon cup. They used a standard addition technique to minimize matrix interferences.Kharmanova and Pogrcbnyak (717) used a graphite capsule atomizer for the analysis of Bi, Cd, Cu, In, Pb, Sb, Te and TI in sulphide ores. The sample was mixed with graphite powder and placed in the capsule (20 mmX2 mm i.d.). The capsule was heated by an air/acetylene flame and electrothermally by a 0.2-1 kVA source. An integral absorbance value was measured. Cadmium was deter- mined on solid rock samples by Mazzucotelli et al.(1926) with ETA using graphite cups. A standard addition method was used for calibration. Gold has been determined directly in powders (1837) placed in a cavity in a graphite rod. Samples were heated up to 2000 "C in air and Au was determined down to 2X 10-11 g; the method was also suitable for Ag down to 6X 10-13 g. Heinrichs (1660) determined Bj, Cd and T1 in 33 international standard rocks by fractional distillation followed by ETA.Samples of 100 mg were introduced into a tube furnace at 1000 "C, the furnace was then flushed with a mixture of N+H and the tempera- ture slowly raised to 1200 "C. Volatilized matter, collected in the cavity of a cold-finger condenser, was dissolved in HNO, and H,O, then analysed with a carbon furnace atomizer.The determination of heavy metals by AAS has been extensively studied by several authors this year. The most popular method of dissolution appears to be by acid attack with mixtures of HF, HNO, and HClO,, although Nuhfer and Romansky (473) investigated fusions with LiBO,. They concluded that samples should be fused above 950 but below 1100 "C to ensure the retention of Pb.Chow (505) preferred a pyrosulphate fusion for Pb in columbite concentrates; this was followed by a sulphide separation in the presence of added Cu. The solutions were analysed by FAAS. Heinrichs (1627, 2035) investigated in detail the interferences from matrix effects on the determination of Pb in HCI and HNO, media. He found that with ETA the effects were negligible in HNO, solutions, but strong suppression of the Pb signal was caused by the chlorides.This could be eliminated by replacing the N purge gas with a mixture of N+H (4+ 1). The determination of As in geological materials was described in three papers (472, 528, 1680). The authors all used hydride generation as a separation technique and finished with ETA. In a method developed by Kobayashi et al.(1589) for Bi in sulphide o m , bismuthine was generated with sodium borohydride and the Bi atomized in an Ar/H, diffusion flame. The fluorescence signal, excited by a Bi electrodeless discharge lamp, was measured. The detection limit was given as 0.005 ng ml-1. Chaudhry and Johnson (729) separated Au from solutions by simultaneously reducing it and Hg with SnCI,.The resultant bead of amalgam was dissolved in aqua regia for analysis by AAS. Several papers have been published on the determination of trace eleme~ts in coal (166, 215, 216, 576, 578, 1335). Of these *e most novel approach was that reported by Messman et al. (1335). They described an AAS technique utilizing graphite furnace atomization for the determination of Cd, Cr, Cu, Pb, Mn, Ni, V and Zn in coal, A high intensity continuum primary source was used in conjunction with a wavelcngth-modulated echelle mono- chromator (see also Section 2.5.2).Various atomic lines were investigated for each elcmmt, and optimal conditions of analysis were established.b Table 4.4 MINERALS L.-. U Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. 3 Form -.Ag - Rocks and minerals 0.1-1.1 p g / g A A 328.1 Ores - Ag Ag 328.1 Copper ores - Silicate rocks - Silicate rocks - Ores, rocks 328.1 Rocks 0-02-0-1 pg/ml A ( i n extract) Trace levels 5-145 ng/g A Ag 328.1 Sulphide ores - Ag 328.1 Rocks 1-5000 ng/g A Al - Venezuelan laterites O h levels A L L L S S S L S S L Decompose with HF/HNO,/HCIO, and F Air/propane 31 2 extract Ag into MIBK, at pH 11, using 2-(2-pyridylazo)-2-naphtholate Comparison of two extraction methods : F - 686 (A) Kl/isoamyl alcohol (B) NaDDC/isomyl alcohol (preferred) Digest with HF/HNO, at 160 "C in PTFE F Air/qH, 1155 bomb, evaporate to dryness and dissolve t y successive treatments with HNO,, H,BO,/HNO, and dilute HNO .Extract Ag with 0.01M TPP/MIBK Grind to 5 pm particle size and atomize 1201 directly Study of spectroscopic buffer effects.A D.c. arc 1255 CaF,, LiF and Li,CO, recommended for determination of Ag and Cu Direct met hod F Air/C,H, 1274 Graphite furnace ( + Fe screw) Graphite furnace (HGA-2100) Digest in PTFE beaker with HF/HNO,/ Graphite furnace 1575 HCIO, and allow to evaporate to dryness overnight at 40 "C. Dissolve residue i n tartaric acid and extract Ag with diphenylthiourea into butyl acetate Mix (1 : 1) with graphite powder, place F Air/C,H, 1607 i n graphite crucible, cover with further graphite powder and heat electrically t o volatilize Ag Mix (1 : 1) with graphite powder, dry at 150 "C, ash at 1000 "C and atomize at 1800 "C (Ag) or 2000 "C (Au) Dissolve in HF/H,BO, to determine At, F - 976 Si, Fe, Ti.(Comparison with XRF and chemical methods) Graphite furnace Graphite furnace 1837 c ww Table 4.4 MINERALS- continued Element A/nm Matrix Concentration Tech* Sample treatment Atomization Ref. 8 Form A1 - llmenites As 197-3 Rocks, soils As As As As Au Au Au 197-3 Geological materials 234.9 Sediments - E L Up to 200 ng A G (absolute) Trace levels A G, L - - Rocks 193.7 Rocks, soils, sediments - 267.5 Rocks 0-01-1 pg/g - Ores From 20 ng/g 242.8 Tailing solutions From 10 ng/g E G - - A L E S A L A L Fuse with Na,CO,/NqB,O,, extract with P - 1149 HCI/H,SO, and dilute Digest with HCI/HNO, at 90 OC, Heated quartz tube 472 evaporate almost t o dryness and dissolve i n HCI (1 : 1).Add KI 4- ascorbic acid, followed by NaBH, Digest with HCIOJHNO,, evaporate almost to dryness, dissolve i n HCI and add KI + SnCI, + Zn powder.Absorb evolved hydride i n AgNO, solution Freeze-dry, pulverize and mix with 20% P D.c. plasma graphite powder + 15% CaSO,. Transfer 30 mg portion to graphite cup in induction furnace, heat to 600 "C i n HCl/argon flow and collect AsCI, in cold trap. Vaporize subsequently at 200 "C and pass AsCI, to arc Graphite furnace (CRA-63) (argon) - - - Digest with HNO,/HCIO,, reduce with Graphite furnace NaBH, and collect ASH, vapour i n AgNO, (CRA-63) so I ut ion Extract sample with HCI/HNO, and A 12Ad.c.electrolyze (+ 0.2 V, 1 h) to deposit Au on to graphite electrode Separate and concentrate Au from ore F - solution by SnCI, reduction in presence of Hg. Dissolve Hg ( + Au) globule i n HCI/HNO, Filter, add NiCI, solution as releasing agent and NaCl solution as an interference suppressant, dilute with aqua regia and determine Au by standard addition technique.Dry at 90 "C, ash at 900 "C and atomize at 2400 "C Graphite furnace 52 B 1471 1511 1680 32 $ Q G- % 729 k 3 1605 '' h x 2 GY 0- Au M ol y bde ri i tes From 5 p / m l A ( i n extract) Au 242-8 Rocks 0.001--1 pg/g A Au 242.8 Ores Trace levels A Au - Ores, rocks Trace levels A Au 242.8 Geological samples Up to 500 oz/ton A 267.6 B Ba Be B i Bi Bi Bi 249.7 Rocks and minerals 455.4 Geological samples 234.9 Meteorities ng/g levels - Geochemical samples Trace levels - Ores, rocks Trace levels - Rocks 223.1 Rocks ng/g levels E E - A Bi - Sulphide ores - F L S L L L S S L L S - L L, G Fuse with Na,O,/Na,CO, (4 : l ) , dissolve Graphite furnace in 1M HCI and extract Au, Pd with petr o le urn s u Ip h i des/t o I uene See Ag, ref. 1837 Dissolve in HCI/HNO, (3 : 1 ) . Graphite furnace Graphite furnace (Interference study) (HGA-72) Study of errors F Digest with HCI/HNO, and dilute with 3 N HCI (10 g sample to 100 mi). Extract aliquot with MIBK and wash with 0.18N HCI before aspiration of the organic phase Mix (1 : 2) with graphite powder F A containing 30% SrSO, + 0.3% GeO,.Use Ge 249.8 nm as internal standard line Mix powdered sample (4 parts) with graphite powder (20 parts) + AgCl (1 part). Excite 30 mg portions i n graphite anode. Use Ag 547.2 nm as internal standard wavelength. Prepare standards i n matching matrix A - Air/C,H, 15 A a.c. 15 A d.c.Graphite furnace - For FAAS, concentrate Bi by extraction. F - For ETA-AAS, optimize ashing stage See Ag, ref. 1274 F Air/C,H, Graphite furnace ( + Fe screw) Graphite furnace cn 1802 6. E s -. 1837 0 1838 1883 1982 1606 780 795 985 1274 1511 1570 - - - Decompose with HF/HCIO,, extract Bi as Graphite furnace back-extract with EDTA, using NH,OH.HCI t o prevent extraction of Fe(1ll) Dissolve in HCI/HNO,, add NH, citrate F Air/Ar/H, 1589 solution, filter and reduce with NaBH,. (Non-dispersive AFS system) iodide complex into MIBK and (HGA-2100) c w w- Table 4.4 MINERALS- coiitirzued Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref.Form Bi 223.1 Standard rocks Trace levels A Ca Ca Cd Cd Cd CI co c o c s - Silicates, laterites 422.7 Silicate rocks - Ores, rocks 228.8 Standard rocks 228.8 Rocks and minerals 326.1 328.1 Carbonate rocks 240-7 Geological samples (Ag 1 - Silicate rocks - Silicate rocks Trace levels Trace levels Trace levels u p to 0.1% 5-1 000 lug/g Trace levels Trace levels A A A E L L L S L S L L L L Place sample in SiO, boat and heat to 1200 "C i n furnace.Collect volatile products in cold trap and extract with HNO,/H,O,. (100 mg sample to final volume of 1 ml) Add H,BO, to HF matrix to overcome F - 702 interference effect from common elements Dissolve with HF/HCIO,.Results for Ca F Air/C,H, 1927 and Mg compared for : (A) Air/C,H, flame, with La releasing (6) N,O/C,H, flame, wkh L i ionization See kg, ref. 1274 F Air/C,H, 1274 Graphite furnace 1660 N,O/C,H, agent buffer ( + Fe screw) Graphite furnace See Bi, ref. 1660 Graphite furnace 1660 Direct method, calibrated by method of Graphite furnace 1926 additions. For Cd below 5 pg/g, use 228.8 nm; otherwise 326.1 nm Add excess AgNO, to sample solution, F - 338 filter and measure residual Ag Digest with HF/HNO,, evaporate, F Air/C,H, 1561 Q- redissolve in HCI, evaporate and dissolve k! 2. i n 2M HCI.Add NH,F to mask Fe and Al, and extract with NaDDC/MIBK, at pH 6 Treat with HF/HCIO, and pass extract of F - 1899 ,b residue through Bio-Rad AG 50W, X-8 resin column. Strip Co from column with b 1M HCI solution in acelone Dissolve by fusion with Na,CO,/NaNO,, F - 676 2 followed by HNOJNH,NO, solution. Dilute, add 50% tungsto-phosphoric acid solution, filter and dissolve precipitate in alkaline borate buffer solution k s ?. $ 2 0c u c u P Fe FO Fe Ga Ge Hg In b 1255 "g - Silicate rocks 324.7 Geological samples 529.3 Geological samples (CaF band) - Silicate minerals - Venezuelan laterites - llmenites 287.6 Manganese nodules 265.1 Rocks 253.7 Rocks, soils, sediments 303.9 Rocks and minerals K 769.9 Rocks and minerals 0.05-1 O/o L i 670.7 Geological specimens - (Isotopes) E S A L E S A, E L A L E L A L A L F G E S E L E S See Ag, ref. 1255 A D.c. arc See Co, ref. 1561 F Air/C,H, Mix sample with Ca(OH), to ensure A D.c. arc conversion of all F to CaF, and excite in special adjustable electrode Dissolve in HCI/HCIO,. (Study of method F of standard additions for both AAS and FES methods) Air/C,H, See Al, ref. 976 F - See Al, ref. 1149 P - Crush and dry at 110 "C.Dissolve, add F Air/C,H, TiCI, and adsorb on Dowex 1 (chloride form) column. Elute Ga with HNO, (1 : 3) Digest with HF/HNO, under pressure at 100 "C. Cool, add HCI to a final strength of 9N HCI and extract GeCI, with CCI,. Back-extract with H,O Digest with H,SOJKMnO,, filter and reduce with SnCI,. Heat sample with SiO, gel and AI,O,. Collect Hg on gold and re-heat to evolve Hg ( A ) In content 1-300 pg/g-Grind. mix A 16 A a.c.W-tube furnace Cold vapour with KI (1 : 1) and transfer to electrode cup (El) I n content below 1 pg/g-Dissolve i n HF/HBr, evaporate, repeat and dissolve residue in HBr. Extract I n with butyl acetate, back-extract with HCI/H,O,, evaporate with KI + C powder Dissolve with HF/HCIO, and add MgCI, F Air/CH, as buffer.(25 g/l in final solution) Introduce powdered sample or dry residue from evaporation of sample solution to hollow-cathode source. (Liquid-air cooled, He + Ar atmosphere). Record hyperfine structure of Li 670.75 nm via Fabry-Perot interferometer Hol low-cat hode (up to 20 mA) 1561 3 1540 g. 2 344 976 1149 1577 497 2 142 339 17 w wC L Table 4.4 MTNERALS - catzliriued Element X/nm Matrix Concentration Sample treatment Atomization Ref.s Tech. Anaiyte Form - Silicates, laterites - 285.2 Silicate rocks - Mg Mg Mn - llmenites - N i 232.0 Geological samples 5-1 000 Pg/g Ni 232-0 Manganese nodules - 0 s 290.9 Magnetic pyrite ores 0.1-0.4 fig/g 305.9 Pb Pb 217.0 Rocks, sediments 217.0 Colombite Pb - Geological samples 0 * 1-1 000 pg/g Pb 283.3 ROCI~S 0-04-0.24 g/ml ( i n extractf Pb - Geological materials - Pb 283.3 Geological materials Trace levels A A E A A E A A A A A A Pd - Molybdenities Pt 265.9 Ores 306.5 (ng/ml in extract) - A L L L L L S L L L L L L L - A.E L See Ca, ref. 702 F - See Ca, ref. 1927 F Air/C,H, See Al, ref. 1149 P - See Co, ref. 1561 F Air/C,H, Dissolve in HF/HCIO, in PTFE bomb. F Air/C,H, Adsorb on Dowex 1 (chloride form) column from medium of 5% 12M HCI 4- 95% C,H,OH and determine Ni i n effluent Fuse with Na,O,, extract with H,O + A - K,Cr,O, + H,SO,, distil solution to evolve Os, Ru as tetroxides and absorb into aqueous dimethylformamide solution of 2-mercapto-benzoxazol.Evaporate on to graphite electrode for analysis Fuse with LiBO, at 1000 "C, dissolve melt in HCI, add HF, filter and dilute to volume (0.2 g/250 ml) Sieve to 2UITmesh size, fuse with K,S,O, and extract melt with tartaric acid.Add Cu solution, pass H,S and filter. Ignite, digest with acid, filter and dilute Review and comparison of ETA-AAS with anodic stripping technique Dissolve in HF/HNO,/HCIO,, evaporake and dissolve in HCI. Extract Pb with DDTCjxylene and back-extract with HNO, Interference study Graphite furnace Digest with HF/HNO,/HCIO, in PTFE Graphite furnace See Au, ref. 1802 Graphite furnace Review of methods, including ETA-AAS A - (255.9 nrn) and OES (306.5 nm) Graphite furnace N O/C,H2 Graphite furnace F Air/C,H, Graphite furnace Graphite furnace bomb (HGA-70) (HGA-70) 7 02 1927 1149 1561 1673 36 473 505 659 5 8 1592 1627 k 3 2035 6.k 1802 3 1590 3 0 0RU 306-5 Magnetic pyrite ores 0.1-0.4 pg/g E S 190.0 Coal fOOpg level E (absolute) Sb 217.6 Ores and concentrates Above 0.01 9'0 A Se - Rocks Se 196.0 Pyrite 0-200 ng/g A ( i n extract) A Si - Minerals - Si Si Sr Sr Sr Te - Venezuelan laterites - Minerals - Geological materials 407.8 Geological materials 460.7 Silicate rocks 214.3 Rocks 9'0 levels - Trace levels 0*005-0.25% ng/g levels A A S S , G L - L L L L L S L L See Os, ref. 36 A - Heat sample in furnace and pass vapour P MIP to plasma i n argon stream Co-precipitate Sb with Fe/La hydroxides F - and dissolve i n HCI (2450 MHz) - - - Digest with HNO,/HCIO,, evaporate to dryness and redissolve in HNO,. Pass through Dowex 50 W-X8 column to remove Fe interference Method for crystalline SiO, content : P N,0/C,H2 Treat with HCI/HNO, to remove acid-soluble SiO,, followed by KOH to remove amorphous SiO,.Filter and fuse residue with NaHCO, + NaCI. Dissolve melt i n Na,CO, solution and add NaCl t o final solution t o give Na concentration of 9500 pg/rnl Graphite furnace (HGA-2100) See Al, ref. 976 F - Method for determination of crystalline F N,0/C2H2 SiO, : Treat with HCI/HNO, to remove acid-soluble silicates and with KOH to remove amorphous SiO,.Filter and fuse residue with NaHCO, + NaCI. Dissolve melt in Na,CO, solution and adjust Na concentration i n linal solution by addition Gf NaCl Graphite furnace - See Ba, ref. 780 A 15 A d.c. Dissolve in HF/HCIO,, evaporate, F N,O/C,H, redissolve in HCI and add 1% La Digest with HCI/HNO,/HF. evaporate to Graphite furnace dryness and dissolve in 6M HCI.Remove (HGA-2000) Fe by cupferron/e:hyl acetate extraction. Add MIBK to aqueous phase t o extract Te and back-extract with H,O - b 36 2 1331 sa 2. 1591 8 1511 1584 405 976 1105 385 780 1910 321 I-. wc. Table 4.4 MINERALS- corzli~zuec! w oa Element X/nm Matrix Concentration Tech. Sampie treatment Atomization Ref. Form Ti - Venezuelan laterites T i - llmenites Ti 364.3 Laterites: silicate rocks TI u V - Standard rocks 424.2 Phosphate rocks 318.5 Bituminous shales and shale-oils V 318.4 Rocks Phenolic and 589.0 Coal and lignite residues Carboxyl (Na) contents (Indirect) Various - Ores, rocks (Noble metals) Various - Cu/Ni ores and products (Noble metals) YO levels - 4-70 pg/ml (in extract) Trace levels - - Trace levels 0.1-6 mg/g (Na+ equivalent) Trace levels cLg/g levels A E A A E A A E f E L L L L t L L L S S See Al, ref. 976 F - 976 See Al, ref. 1149 P - 1149 Treat ground sample (I50 mesh) with F N,0/C,H2 1737 1901 Dilute and add H,EO,. (Comparison with XRF and colorimetric methods) See Bi, ref. 1660 Graphite furnace 1660 Extract with TOP0 P D.c. arc 1436 ( A ) For shales, ash at 500-600 "C, fuse F N,O/C,H, 977 HCI/HNO,, followed by HF, at 90 "C.(argon) with Na,CO, i- K,CO,, dissolve i n Graphite furnace HCI and extract v' with dithizone into MIBK, at pH 1-5-2.5 (FAAS) and extract with H,O, for measurement ( B ) For shale oils, combust in 0,-bomb by ETA-AAS Decompose with HF/HNO, i n PTFE W born b, evaporate to dryness, dissolve in HCI and extract V as N-benzoyl-N- phenylhydroxylamine complex into CHCI, Treat with 1 N NaOH, wash thoroughly and extract retained Na+ with HCI, to determine total acidity F Mix with graphite powder + NaCI, A BaCO, and excite by cathode-layer method.Elements quoted : Ru, Rh, Pd, Os, Ir, Pt, Au Pre-concentrate &g amounts of Ru, Os, Pd, Pt, Ir, Rh and Au from sulphate medium by treatment with HClSchelating resin. Boil, add graphite powder, filter, moisten resin +graphite residue with Na,S04 solution and ash at 500 "C.Continue by spectrographic method (see AXAAS, 1975, 5, Ref. 1158) A micro-furnace 1674 - 565 A.c. and 13 d.c. arcs - 770W Various - (Alkalis and alkaline earths) Various - (Rare earths) Various - (Noble metals) Various - (Rare earths) Various - (Rare earths) Various - (Noble metals) Various I (9) Standard rocks Geological materials Effluents and process solutions Minerals Minerals Ores Silicate rocks Silicate rocks and minerals Igneous rocks Minor and E trace levels All levels E pg/ml levels E Various levels E pg/ml levels ( i n extract) A A Oh levels A, E All levels E YO levels (7), E minor levels (3) and trace levels (8) Mix powdered sample with Cu powder and form briquette discs.(Photodiode detector system) Fuse with Na,O, or LiBO, and extract P ICP with HNO, or, alternatively, digest with HF/HCIO,. For trace R.E. levels, fuse with K bifluoride and concentrate by ion-exchange (Biorad AG 7-X8) Separate precious metals from matrix P ICP elements (Na, Ca, Fe, Ni, Zn) by precipitation and redissolve i n HCI/HNO, or by Na,O, fusion Decompose with HF i n PTFE pressure A 6 A d.c.vessel at 180 "C. Evaporate and mix residue (largely CaF,) with graphite powder + Pd internal standard. (342.1 nm). Results given for Sc, Y, La + 13 rare-earth elements - P ICP Glow discharge lamp (N,-cooled) Digest with HF/HNO,, evaporate, fuse with excess Na,O, at 700 "C, dissolve i n HCI, evaporate, redissolve in 3M HCI and extract aliquot of diluted solution with 0-5M alkylaniline/toluene.(Au, Pt, Pd, Rh, Ir, Ru) (A) Digest with HF/HCIO, and determine F Air/C,H, Graphite furnace (HGA-74) Ca, Fe, Mg, Mn by AAS and Na, K by FES, with air/C,H, flame N,O/C,H, flame, adding Na, Fe, A1 t o Ti standards and Na, Fe to A l standards (C) Fuse with Na,CO, for determination of Si N ,0/C2H2 (8) Determine Ti, A1 by AAS, with Crush and dilute with graphite powder.A D.c. arc (Automated read-out system) Fuse 200 mg sample with LiBO, and P D.c. arc dissolve melt in HNO,/H,O ( 1 : 24) containing 0.4% CsCI. Calibrate against standard reference rocks plasma 807 2 ;i' 869 x h 871 975 1476 2065 4 6 58 c. WTable 4.4 MTNERALS- corrrirzucd w $ Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref.Form Various Various (11) Various Various (16) Various Various (9) Various (14) Various Various Various (70) ( 9 ) Various Various (10) Coals and mineral wastes Bituminous coal Geochemical materials Coal Coal Standard rocks Standard rocks Geochemical materials Ores; coal; geological samples Geochemical materials Coal and gasification plant products Coal and liquefaction plant products Trace levels E, A S, L - A, E L AII levels All levels E A Trace levels A Trace levels E Trace levels A Trace levels A S L/S L L L L - A, E L/S All levels E L Trace levels A L Trace levels ( 4 ) and A L minor levels (6) Review of methods and techniques, including OES and AAS - - - F - 60-channel D.R.system A D.c. arc Powder (< 325 mesh) and prepare P Air/C,H, slurry (0-1-15 g/loiO ml) for direct flame or furnace injection Graphite furnace N,0/C,H2 Statistical analysis of interlaboratory F results for Cd, Cr, Pb, Zn Study of sample treatments, including separation of major constituents and use of radio-tracers to monitor losses P Analytical scheme based on stepwise solvent extraction to isolate groups of elements F Study of interference effects P Slurry-injection system.Pulverize sample F t o 325-mesh size and form slurry (0.1-8°/~ m / V ) in 0.5% Triton X-100 medium Computer-controlled sequential sysiem P Investigation of distribution of trace elements (As, Se, Sb, Hg, Pb, Cd, Ni, Cr, Be) Graphite furnace Investigation of distribution of trace (Cu, F - Cr, Ni, Mn) and minor (Fe, Si, Al, Ca, Mg, K) elements Graphite furnace 87 166 203 21 5 21 6 231 324 51 1 530 $ Y 3. 9, % 561 576 $* el 578 5 0 'h 5 2 olVarious - Manganese nodules Various levels A L (15) Various - Sulphide ores ( 8 ) Various - Geological materials - Various - Silicate rocks Trace levels (13) Various - Standard rocks - Various - Geochemical samples 0.1-10 yS/g (6) Various - Ores (6) p g / g levels A S E L E S - - A L E L Varlous - Sulphide concentrates Various levels A, E L, S Various - Igneous rocks Trace levels E L (A) Dissolve in HCI/HNO,, filter and F Air/C,H, dilute (rapid method for Mn, Fe, Cu, Ni, Co, Pb, Zn) (6) Fuse with Na,CO,/H,BO, and dissolve melt in HCI ( 1 : 3) (standard method for Si, Al, Mn, Fe, Cu, Ni, Co, Pb, N,0/C2H2 Zn 1 (C) Treat with HCI/HF/H,O, in PTFE beaker, evaporate, redissolve in HCI and add La and Al solutions before dilution to volume (standard method for Ca, Mg, Na, K, Ti, Sr) Dilute with graphite powder and take F Air/C,H, 50 mg portions for analysis, in graphite capsule inserted into flame Review Study of matrix effects A A.c.arc + heated graphite cell P ICP Review of elemental abundance data for - - standard rocks, i n relation to analytical methods used Dissolve in HNO,, dilute to 25% HNO, F Air/C,H, strength, centrifuge and aspirate.(Cu, Pb, Zn, Ag, Co, Ni) ( A ) Decompose with HCI/HNO,/H,SO, A Solution- (2 : 2 : l ) , evaporate twice to fuming with HNO,. dissolve in H,O and add, in final volume, 0.5% KCI + 5% isopropyl alcohol. (Method for Cu, Ga, I n , Mn, Ni) (B) Fuse with Na,O, + NaOH, dissolve in H,O, neutralize with H,SO, and evaporate.Extract with CCI, and back-extract with H,O. Add 10% isopropyl alcohol i n final solution spray in stabilized arc Review of methods A, F - Study of geochemically coherent P ICP element-pairs ( e . g . , Hf/Zr, Mn/Fe) with analytical precision of 1-2% and relative accuracy 97-98% 697 2 =: e 2 -. 0 71 7 728 750 752 762 778 787 867 + P cTable 4.4 MINEiRALS- corztiizued ~ ~ ~ ~~~ ~~~ Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref.Form Various - Geochemical samples - E Various - Geological materials YO levels (10) Various - Rare-earth ores and All levels concentrates Various Varlous (7) (20) Various ( 8 ) Various Various Various Various Various (42) (19) - Geological samples - Geological samples - Coal - Coal slurries - Rocks - Limestone - Geological reference - Coal (fly ash) samples Trace levels - All levels Major levels All levels Trace levels E E A E - E - A L L L S S - L - S - L Simulianeous multi-element system P ICP 868 ( x 10000 for 0.2 g sample).Method designed for major constituents Si, Al, Fe, Ti, Mg, Ca, Na, K , Mn, P ( A ) To determine Si, AI, Fe, Ca, Mg, Ba, F N,O,/C,H, 921 Dissolve in HF, add H,BD, and dilute P ICP 881 Sr fuse with Na,CO, and analyse by f lame-AAS wet-ash with H,SO, and separate R.E.elements as oxalates for flame-AAS analysis Graphite furnace (B) To determine R.E. elements (12) (These procedures are also compared with ETA-AAS) corrections (Si, Al, Fe, Mg, Ca, Na, K) Inject axially, as fine powder P Two-stream 986 Statistical evaluation of interelement A - 978 plasmatron (d.c.) Graphite furnace Elements studied : Cd, Cr, Cu, Pb, Mn, Ni, V, Zn - P - 1361 Discussion of differences between “whole - - 1457 rock” and “whole ash” analyses of sed imentary rocks Crush, mix with Cu powder and form Glow discharge 1473 briquettes.(Application of photodiods source array system) Report on composition of 6 new USGS - - 1554 Geochemcial Exploration Samples Room temperature dissolution method : F Air/C,H, 1567 Weigh 1 g sample into 100 ml screw-top polypropylene volumetric flask, shake N,O/C?H, overnight with 10 ml H20 + 10 ml HF, add 80 ml saturated H3fi0, soluilon and re-shake (4 h ) .Filter off any residue (Cd, Co) 1335 (8 elements) (9 elements) Graphite furnaceVarious - Rare-earth minerals I Various - Geological materials All levels (17) E L E L Various - Coal (6) Various - Silicate rocks Various - Ores (7) Ail levels All levels - Various - Silicate rocks All levels Various - Geological standards - (5) Various - C hr am i t 8 Various - Coal ash (8) Various - Iron ores (8) A L/S E L E L A L A L A L A L Trace levels A L Various - Coal Trace levels A L Study of matrix effects due to flux material (Na,B,O,) (Comparison of alternative plasma P systems) (A) Dissolve in HF/HCIO, and dilute t o (B) Fuse with LiBO, and dissolve in Grind (325 mesh) and prepare slurry in H,O/Triton X-100 (O.SO/O).Elements : Fe, Zn, Cu, Ni, Sr, Cr Fuse with LiBO, at 950 "C and dissolve in HNO,, with CsCl added Treat 1 g sample with 4 ml conc. HCI + 1 g KCIO,. Boil, cool, add 8 ml of 20% ascorbic acid/lO'% K I solution and extract with 5 ml of 10% Aliquat-336 i n MIBK, by centrifuge. Elements : Ag, Au, Bi, Cd, Cu, Pb, Zn Fuse with LiBO, at 1050 "C and dissolve melt i n HNO, with additions of CsCl and HF. Dilute to volume after 24 h Digest in HCI/HNO, (3 : 1 ) . (Study of interferences in determination of Cd, Cu, Ni, Pb, Zn) P volume in 2% HNO, 2% HNO, F P P F F Fuse with K,S,O, + K2S,0, F F (A) Digest with HCI/HF in PTFE bomb and dilute with 4% H,BO, (for Si) (B) Digest with HF/HCIO, in PTFE bomb, evaporate to dryness, dissolve i n HCI (for Na, K, Mn, Ca, Mg, Af, Fe) lnterlaboratory study of sample treatment. F (A) Digest with HCI (B) Fuse with Na,BO, + Na,CO, and dissolve in HCI Review (23 refs.) comparing MS, AAS F I CP ICP and MIP - D.c. arc plasma I CP Air/C,H, N,0/C,H2 Air/C,H, - Air/C,H, N,0/C2H, - - A 1654 'tJ 1691 g. g G1 1694 1710 1742 1755 1760 1776 1812 1898 1906w Table 4.4 MINERALS- continued P P Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form Various - Silicate rocks ( 6) Various - Rocks and minerals (alkalis) Various - Iron ores (13) Major levels A L Fuse with Li,CO, -t H,BO,. Match standards for fusion matrix and add Ba for Al, Mn determination. Elements : Si, Al, Fe, Mg, Ca, Mn interferences in the determination of Li, Na, K, Rb, Cs E S, G Prepare briquette with Cu powder and vapourize from graphite cup electrode, using a.c. arc. Pass vapours to ICP in stream of argon A C, G Review of methods, including Cu, Zn, Pb, Co, Ni, Li by FAAS; Au, Sb, Hg, As by specialized methods A L Study of physical and chemical Various - Silicate rocks and minerals Trace levels (10) Air/C,H, 1912 N 20/C,H, Air/C,H, 1919 N,O/C,H, I CP 2028 - Cold vapour Heated cell 2071

ISSN:0306-1353    

DOI:10.1039/AA9790900127

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

Applications 145 4.5 AIR ANALYSIS No major advances have occurred in this applications area during the past year, most publications once again concentrating on modest improvements and refinements. Although many of the reports were concerned with optimization of analytical parameters, greater interest has bcen shown in devising improved methods for sample preparation and pretreat- ment, which are intended to avoid limitations of the measurement technique.Much more chemistry is being used in conjunction with instrumental techniques than for many years, particularly chemical and chromatographic separations for speciation studies. In spite of continuing uncertainty as to the accuracy of all methods of analysis at trace levels, there has been little new effort directed towards this aspect of air analysis.Hanrtz at al. (1 1 9 , however, organized a collaborative study, involving 17 laboratories and 25 samples, of a standardized FAAS procedure for the determination of Cd, Coy Cr, Ni and Pb in dusts collected in workplace environments. Other workers have compared the use of XRF and AAS for the analysis of urban dust and fly ash samples (367, 61 1). 4.5.1 Sample Preparation The collection of volatile species has received much attention. For Hg, amalgamation (see also 957, 1581, 1777) with Au was found to1 be preferable to the use of activated charcoal or Ag-coated sand (1462); different methods for the preparation of Au-coated glass wool have been described (1664). Satisfactory absorption of Hg has been achieved with KMnO,/H,SO, (1251, 1766) and MnO, and cellulose/activatcd charcoal (1666).Gaseous alkyl-Pb compounds have been collected either at low temperature (1792) or in iodine monochloride solution (1668). A solution of AgDDTC in pyridine has been used as a trap for SbH, (1646). A special apparatus was designed for the €€NO,/HClO, digestion of dust samples on filters (346). Stratton and Routh (1597) evaluated the suitability of a number of digestion and extraction systems for use prior to ETA and hydride-generation AAS determinations of As and Se.A study has also been made of As losses during the ashing of particulate samples (1 945). - As mentioned earlier, chromatography is now frequently used in speciation studies. A GC with a portable d.c. plasma detector was used for the determination of organo-Hg compounds by AES (538).A GC with an ETA-AAS detector has been applied to the measurement of alkyl-Pb compounds (1562). In the latter instance, the GC was connected by a small Ta tube to the furnace, which was operated continuously at 1500 "C. Ion- exchange chromatography was used to separate Cr(II1) and Cr(VI), the latter being carcinogenic, in aqueous extracts of welding fumes prior to the determination of Cr by FAAS (1497). 4.5.2 Atomic Absorption Methods The direct determination of metals in air particulates using electrothermal atonzizatiorz has been reported, segments of filter material being placed either directly in the furnace tube or introduced on small graphite boats (269, 298, 438). Efforts are still being made to identify and overcome interference effects in ETA.Geladi and Adams (1560) completed a detailed invcstigation of interferences in the measurement of Be and Mn in aerosols: HC10, caused a particularly serious problem when used in digestion procedures prior to ETA and it was recommended that its use be avoided or that it be removed before the determination. Additional references on the preceding topic - 362, 394, 1630.In the determination of Cry Cu, Fe, Mn and Ni by flame afontic absorptioir spectro- scopy, excellent precision and 98-102% recoveries were obtaincd aftcr simple mineraliza- tion of filters with HNO, (723).146 Analytical Atomic Spectroscopy 4.5.3 Atomic Emission Methods The main interest in emission spectroscopy continues to be in multi-element determinations using the ICP source.This technique is now sufficiently well established for detailed appraisals to have been made, and its limitations, as well as its potential, are becoming more apparent (958, 1 125, 1259). New reports of traditional emission spcctrographic analyses are less common in this field, but reports have appeared of the determination of 15 elements in dust falls (637) and of 14 elements in airborne matter with RSDs of 0.014-0.15 (1677).A CMP has been described that used ambient air as the plasma gas to allow the direct determination of airborne Hg and Pb at levels of 30 and 20 pgm-3, rcspectively (537). It was necessary to compensate for severe background emission, and this was done by a novel correction system in which the emission was passed through a sealed absorption cell containing Hg or Pb vapour.Patterson (1465) used a modified AA spectrometer with a simple algorithm to determine Cay K, Li and Na by FAES over wide conccntration ranges. It was claimed that only two standards were required. 4.5.4 Atomic Fluorescence Methods Non-dispersive atomic fluorescence spectroscopy has been applied to the determination of Cd.Fey Pb and Zn on air filters (1578).Table 4.5 AIR AND PARTICULATES b 2 Element h/nm Matrix Concentration Tech. Sample treatment Atomization Ret. F Form As As Be Cd ~~~ ~ - Industrial atmospheres ng lbvels (absolute) - Airborne particulates - 234.8 Aerosols 0.03-3 ng (absolute) 228.8 Cigarette smoke Trace levels A G A L A L A L, S Cd Cd C3 Cd Cr Cr Cr Cr Cr - Atmospheric dust Trace levels - Air ng-pg levels (absolute) - Urban dusts - - Airborne particulates 0.2-1.4 pg/m3 - Welding fumes - - Atmospheric dust Trace levels - Working atmospheres 0-2-10 pg/ml (in extract) - Welding fumes - I Urban dusts - A t A L A - F S A L A L A L A L A - Review of various methods for As, with hydride-generation method preferred Collect on glass-fibre filters. (Comparison with NAA results) Collect on filter and digest with HNOJHCIO, or HF/HNO, Collect particulate matter by electrostatic precipitation and dissolve in CH,OH for analysis.Pass gas phase through Millipore-filter discs, for separate direct analysis Collect on filter (0.41 bm), weigh and digest with HNOJHCIO,, Comparison of flame and flameless methods for Cd, Pb, using filtered and digested samples - Collect on filter paper and take 3mm diam.punched discs for analysis. Dry, ash and atomize at 2300 "C i n furnace and sweep vapours to flame i n stream of N,. (Non-dispersive AFS system) - See Cd, ref. 346 Collect on membrane filter and dissolve in HNO, Collect sample on membrane filter. For total Cr, digest with HF/HCI/HNO, i n PTFE vessel, at 100 "C.Add H,BO,, heat, cool and dilute. For Cr(lli)/Cr(Vl), separate by ion-exchange (pH 3-5) - - Graphite furnace 1597 2 B 1945 Graphite furnace Graphite furnace (HGA-74) Graphite furnace F Air/C,H, Graphite furnace - - Graphite furnace F Air/C,H, ( H GA-2000) (N,-sheath) F - Graphite furnace F - F Air/C,H, 1560 298 346 394 1533 1578 327 346 1267 1497 1533 Fe - Welding fumes - A L - F - 327 - 5c Table 4.5 AIR AND PARTICULATES- c o i l t i i i i i c p d P 00 Element X/nm Matrix Concentration Sample treatment Atomization Ref.Form Fe - Aerosols I Fe - Airborne particulates 33-47 pg/m3 Hg 253.7 Air Hg - Air From 5 pg (absolute) From 30CLg/m3 - Air - Hg 253.7 Air 253.7 Air 253.7 Air 253.7 Air 253.7 Air and gases From 0.5 ng/ml (in extract) 7-2600 ng/m3 From 1 ng/mJ A F E E A A A A A A A L S G G G G G G G G G Comparison of AAS and proton-induced X-ray emission methods for Fe, Mn, Pb and Zn See Cd, ref. 1578 Combined GC/plasma emission system Direct method for Hg and Pb, using sample to sustain air plasma torch Draw sample through glass fibre filter (for solid Hg compounds) followed by gold-coated sea-sand absorber (for total volatile Hg compounds).Then : (A) Filter-Pyrolyse under N, at 500 "C and pass vapours over Si0,-gel/ AI,O,/Mg (CIOJ2 cleansing train. Collect Hg on final gold absorber (B) Gold absorber-Heat to release Hg Absorb szmple i n 0.1N KMnO, + 0.1N H,SO, ( 1 : 1) and reduce with SNCIJHCI Comparison of 3 absorbing systems. Au-coated sea-sand preferred Collect sample on Au-coated quartz wool fibre Collect on Au-coated quartz wool and heat to 650 "C (A) Collect by adsorption on MnO, and (B) Collect by adsorption on activated dissolve in HCI/HNO, charcoal + cellulose powder, iqnite F - F Air/C,H, Graphite furnace P D.c.plasma P Air plasma Cold vapour Cold vapour Cold vapour Cold vapour Cold vapour Cold vapour in Wickbold (O,/H, flame) apparatus and condense Hg in cold-trap for AAS measurement by cold-vapour method Collect by H,SO,/KMnO, bubbler, at 0.3 I /min.Oxidize with additional H,SO, + HNO, ( 2 : 1) Cold vapour 395 1578 538 537 957 1251 1462 1581 3 1664 % 1666 6. b -. : tl 1766 7 0 % 2 2Hg Mn Mn Mn NI Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb - Alr From 0.1 ng - Welding lume:s - Aerosols 279.5 Aerosols, fly ash 279.8 280.1 403.1 232.0 Cigarette smoke 217.0 Cigarette smoke - Atmospheric dust - Air I Aerosols - Alr - Dusts - Urban dusts 283.3 Air - Alrborne particulates 283.3 Air - Alr c 0.05-200 ng (absolute) Trace levels Trace levels Trace levels ng-pg levels (absolute) I From 20 pg/m' - A A A A A A A A A E A A A 0 . 5 CL/mj level F A - From 1 ng/rnl A (200 I sample) P Q G L L L L, s L, s L L L G L - G S L L Collect using 2-stage Au-amalgamation gas-sampling train Cold vapour - F - See Fe, ref. 395 F - For aerosols, see Be, ref. 1560. For fly-ash samples, digest with HF/HNO,/ HCIO,. Choice of wavelength provides 4 different concentration ranges See Cd, ref. 298 See Cd. ref. 298 See Cd, ref. 346 See Cd, ref. 394 F Air/C2H, Graphite furnace (HGA-74) Graphite furnace Graphite furnace Graphite furnace Graphite furnace See Fe, ref. 395 F - See Hg, ref. 537 P Air plasma Dissolve filter portion in CHCI, and Graphite furnace extract solution with 2N HCI - - - Combined GC/AAS method, for detecting Graphite furnace Pb alkyls i n air. Collect Pb at -72 "C i n (HGA-2100) PTFE-lined A1 tube packed with 3% OV-101 on Chromosorb W. Release by heating i n H,O at 100 "C. Collect particulate Pb on filter-paper for separate analysis See Cd, ref. 1578 Collect particulate Pb on cellulose filter and trap organo-Pb vapours in iodine rnonochloride solution. Ash filter and dissolve in HNO,. Treat ICI solution with NH,OH/NH, citrate buffer (pH l l ) , add EDTA and extract with dithizone into CHCI,. Back-extract with HNO, Collect alkyl-Pb compounds by adsorption F - on low-temperature (-190 "C) collector; desorb by heating Graphite furnace F Air/C,H, Graphite furnace 1777 2 327 3 2. 395 0 1560 ' 298 298 346 394 395 537 785 1533 1562 1578 1668 1792 II 3 Table 4.5. AIR AND PART~CULATES-conlinueci Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form S S S S (CSJ Sb Sb Zn Zn Zn Various Various Varl ous Various Various Various (5) (8) Various Various (15) Aerosols - Air Air Air Airborne particulates - Air From 0.07 mg/m’ Cigarette smoke Trace levels Aerosols - Airborne particulates 9-15 pg/ml (as SbH,) - Aer oso Is (Workplace environments) Air particulates - Air particulates Trace levels Urban dusts - Particulates - Air particulates - Air particulates - Dust 16-8000 pg/g (various elements) E E E E A A A A F A A A A G G G G L L L, s L S L S L L E, A L, S A S A L E S Flame photometric monitoring system to F - measure particulate S, combined wilh thermal analysis for S-compound speciation Review F - - F - Concentrate on chromatographic support F - treated with Na azide + HMPT Hydride-generation (NaBH,) method F Ar/H, compared with ETA-AAS Graphite furnace Trap SbH, in pyridine/Ag DDC solution Graphite furnace See Cd, ref. 298 Graphite furnace See Fe, ref. 395 See Cd, ref. 1578 F - F Air/C,H, Graphite furnace Inter-laboratory study on performance of F - AAS method for Co, Cr, Cd, Ni, Pb Method uses direct atomization of Graphite furnace - Graphite furnace segments cut from sample filter (HGA-72) Detailed comparison of AAS and F - energy-dispersive XRF methods Review (49 refs.) F, A - Collect on membrane filters and apply portion to furnace in graphite boat Comparison of AAS and XRF methods F - Graphite furnace Collect on filter, dry, grind and mix with A - graphite powder + Ai,O, buffer mixture 336 427 1269 1270 1854 1532 1646 298 395 1578 115 269 % 2. 362 367 % b 437 2. %! 438 r 2 b 611 $ 637 8Various - Welding fumes - (5) Various - Work-place atmospheres - Various - Air particulates - Various - Dusts - (7) Various - Airborne particulates - Various - Airborne particulates - Various - Airborne particulates - (15) Various - Atmospheric dusts - Various - Air (14) Trace levels Various - Atmospheric precipitation ng/ml levels (10) A E E A E A - A E A, E L L L L - L - L S L Collect material from 400 dm3 air sample on membrane filter and wet-ash with HNO,.Dissolve residue in 0.1N HNO, (final acid strength) and determine Fe, Mn, Ni, Cu, Cr Review Study of total and extractable (HCI) toxic metal content of street and household dusts. (Zn, Cd, Pb + 4 other elements) Review Comparison of AAS and NAA methods F Air/C,H, P ICP P ICP F - P ICP F - Collect samples (< 10pm) on low-volume sampler (1 month period). Ash filters at low temperature and mix residue with graphite f In,03 + Pd (internal standard) Results given for Al, As, Cd, Cr, Fe, Mn, Ni, Pb, V and Zn Graphite furnace A - F - Graphite furnace P D.c. arc plasma 723 IA % 2. 3 958 1125 1140 1259 1268 1518 1526 1677 1915

ISSN:0306-1353    

DOI:10.1039/AA9790900145

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

152 Analytical A tomic Spectroscopy 4.6 WATER ANALYSIS Very little has appeared this year that could be described as major innovation. Most of the reported work has dealt with minor improvements to techniques, particularly for sample preparation. Interest in speciation studies continues to increase. The problems of detecting errors in trace analysis of natural waters have been discussed by Stoeppler et al.(1503), who recommended combining the few available CRMs with interlaboratory testing and variation of analytical procedure. This approach was evaluated for Cd, Cu, Hg, Ni and Pb in natural waters, including sea water. Two round robin-tests involving more than 20 working groups in the analysis of sediments for 18 elements revealed accuracies of between 20 and 80% for AAS determinations (2029).The South African National Institute for Water Research has also organized extensive collaborative studies, 16 laboratories determining Ca, K, Mg and Na contents (1452) and 14 laboratories trace metals (1 858). Some individual laboratories have carried out comparisons of diflerent techniques. Neitzert and Lieser (1166) obtained satisfactory agreemcnt bctween AAS, NAA and XRF determinations of 27 elements in standard water samples.Two spectroscopic techniques, AAS using ETA and AES using a d.c. plasma, have been compared for the determination of Al, As, Cd, Cr, Fe, Mn, Ni, Pb, V and Zn in precipitation samples (1915). Grant et al. (544) completed an extensive comparison of FAAS and photon-induced X-ray emission spectroscopy for acid-leachable trace metals in 27 marine sediments.The ratios of the results obtained by the two techniques for Cr, Cu, Fe, Ni, Pb and Zn were found to lie within two standard deviations of the theoretical value (i.e., 1.0) for between 90 and 97% of the determinations. All mean ratios for each of the elements studied were well within two standard deviations of 1 .O. Atomic absorption spectroscopy has been compared with NAA for the determination of Cu and Mn in sea water (498) and with colorimetric methods for heavy metals in sewage and treated ef€iuent (1929).Guidance on selection of methods has been given by several authors. Rodier et al. (1073) produced a comprehensive treatise on water analysis and Smith and Finlayson (668) reviewed rapid spectroscopic methods for trace elements in natural waters.Skougstad (1 205) discussed the requirements for routine measurements of water quality together with the capabilities of FAAS, ETA, ICP-AES, anodic stripping voltametry and fluorimetry. Additional references on the preceding topic - 1206, 1501. 4.6.1 Sample Preparation The current interest in low concentrations of trace metals, particularly in natural waters, continues to emphasize the problems of sampling and storage.Boutron (1885) has described an elaborate procedure for sampling Antarctic snow and Bruland et al. (1070) have compared various sampling techniques for sea water and described a vigorous receptacle cleaning method. It was reported that water and HNO, samples stored unfrozen in thoroughly cleaned high-density polyethylene containers remained uncontaminated after 4 years (1 1).All such precautions are, of course, futile unless losses of trace metals can also be avoided. For example, even after 1 day’s storage, Watling (1557) found it necessary to neutr lize samples and shake them with DDC. Perversely, Cragin (1498) found that such widely used preservatives as HNO, and KMnO, increased contamination of water samples by Hg from ambient air when plastic containers were used.Suitably treated glass bottles have been recommended for sea-water samples to be used for Hg determinations, H,SO, being added as a preservative (477). Procedures for the destruction of organic matter prior to analysis continue to constitute a controversial area. This is particularly so for Hg determinations by the cold-vapour AASApplications 153 technique; the need to break down organo-Hg compounds to determine total Hg is widely recognised, but the success of various oxidation techniques appears to be strongly sample dependent.Irradiation of strongly acidified samples with U.V. light appears to offer the widest applicability, and has been compared favourably with other techniques in several reports (8, 470, 496, 1512, 1719).There are problems, however, if the samples contain appreciable amounts of suspended solids (470). An important advantage of the technique is the low and constant blanks that can be obtained. Alternative techniques for Hg continue to be evaluated (38, 1076). An automatic system for Hg determinations has been described in which 30 samples h-1 can be filtered and oxidized by both acid dichromate and U.V.irradiation (496). The rapid analysis of sewage sludge for toxic metal contents is of increasing importance with respect to its disposal on land. A rapid pretreatment procedure for sewage emuents and sludges involved uZtra-homogeitizarion (1 442, 1568). Direct analysis of the resultant material using ETA compared favourably with conventional wet or dry oxidations followed by FAAS for Al, Cay Cd, Cr, Cu, Fe, Mg, Ni, Pb and Zn.Preconcentration techniques have again been of major interest, particularly for water analysis (670). Solvent extraction systems have been widely reported, but most publications now relate to minor modifications too specific to detail here. Detailed studies of the APDC/MTBK system applied to drinking waters were of particular interest (1 17, 1759).The increase in multi-element determinations has created a demand for single extractions giving good recoveries for as many elements as possible; Bone and Hibbet (1467) succeeded in affecting simultaneous extraction of 10 elements (Cd, Coy Cr, Cu, Fey Mo, Ni, Pb, V and Zn) from aqueous samples using MIBK / 2,6-dimethylheptan-4-one.A novel extraction pro- cedure for very large volumes of water, involving use of a polyurethane foam plug impregnated with 1 -(2-pyridylazo)-Znaphtholy was reported (293). The foam plug was placed in the sample and repeatedly squeezed for several hours. It was then dried, the trace elements extracted from it with CHCl, and finally back extracted into aqueous solution prior to AAS measurements.Zon-exchange methods have received considerable attention, many more publications appearing this year than last. As with solvent extraction an important area of activity is the simultaneous preconcentration and/or clean up of as many elements as possible before multi-element determination. Chelex 100 was used for the separation of 8 elements, Cd, Coy Cu.Fe, Mn, Ni, Pb and Zn, in sea water prior to their determination by AAS using ETA (456). Berman et al. (731) described another ion-exchange procedure for the same elements, also in sea water, which gave sufficient concentration (80-100-fold) to allow Cu, Fe, Mn, Ni and Zn to be determined simultaneously using ICP-AES. The levels of Cd, Co and Pb were, however, still too low in most samples for reliable determination.A new polydithiocarbamate resin has also been evaluated for its potential uses for ICP-AES (1309). Kempster and Van Cliet (37) have described a semi-automated system using Amberlite TR-120H resin for concentrating Cd, Co, Cry Cu, Fe, Mn, Ni, Pb and Zn from water samples, A FAAS system has been described for the determination of Au and Pt in which the eluate was aspirated directly on emerging from the column (229).Tsozaki et al. (1 72) described an even more direct approach, in which sub-ppb Cu levels were determined, after adsorption onto a resin, by placing the resin directly into a graphite furnace ETA system. The resin was dried at 350 "C (20 s), ashed at 1400 "C (60 s) and atomized at 2700 "C (10 s).Electrodeposition is a particularly attractive preconcentration method for determina- tions by ETA. Batley and Matousek (195, 1192) deposited Cr from sea water directly onto the walls of pyrolytic graphite-coated furnace tubes using a flowthrough cell, whereas154 A izaly tical A tom ic Spectroscopy Czobik et al. (1193’) preferred to deposit the analyte metals (Ag, Cd, Cu, Pb and Zn) onto a W wire, which was then passed through a heated graphite furnace.Additional reference on the preceding topic - 1453. A co-precipitation technique has been described in which the difficulties of filtration were avoided by employing flotation. A stream of small gas bubbles was used to form a stable and easily removed layer of precipitate on the solution surface (204).Applications of flotation have also been reported for the AAS determinations of As (1705), Se (1767) and Sn (1 811 3) in water or sea water. Other preconcentrcrtion methods worthy of mention included a non-boiling evaporation system for ultra-trace levels (10+-12 gg-1) of metals in snow samples (4‘65), and the use of precipitate exchange on thin metal sulphide layers as a method for preconcentrating various metals from potable and surface waters and snow prior to AAS determinations using ETA.Speciation of trace element constituents is of major interest in environmental worh and a number of techniques using AAS for the final measurement, often with preliminary chromatographic separations, have been described. Mericam and Astruc (664) have reviewed speciation methods for Cd, Cr, Cu, Ni, Pb and Zn in waters.A combination of GC and AAS has been used to determine tetra-alkyl-Pb compounds (Me,Pb, Me,EtPb, Me,Et,Pb, MeEt,Pb and Et,Pb) in water, sediment and fish samples (1641) and also to study the interaction of Et,Pb with sea water (1796). Six different organo-Sn compounds and Sn(1V) were distinguished by forming the hydrides, which could be separated by exploiting their different boiling points before AAS measurement (1711).Odanaka et cnl. (1 130) used solvent extraction and TIC prior to ETA measurement to determine inorganic and methylated arsenicals. Solvent extraction /AAS has been used for speciation of organoiSi compounds in water (777), organ-Sn in water (449), Te(1V) and Te(VI) in water (1477) and As(1II).Sb(1II) and %(W) in drinking water (13’66). 4.6.2 Atomic Absorption Methods Application reports of conventional FAAS continue to appear, but improvements to instrumentation or methodology are now relatively rare; ETA predominates as the “growth technique” in the field of water and effluent analysis. Manning (662, 1060) has discussed the applicability of AAS techniques to trace metals in water, with particular reference to water quality standards set by the United States Environmental Protection Agency and other U.S.official bodies. A detailed paper on the determination of Cr in waters and sewage by flame utomic absorption spectroscopy paid particular attention to the precautions needed to allow the use of an air/C2H, flame (almost luminous flame and NH,ClO, addition to samples) (509).A report has also appeared of strong spectral interference from Co and Fe in Cs determina- tions by AAS (919). The determination of Cd and Pb in the low ngml-1 range in drinking water, involving use of an electrically heated Pt wire loop to introduce samples into a flame, has been described (1684).Morrow et ad. (19’301) have constructed a fully automated dual- channel microprocessor-controlled AAS system to determine As and Se in natural waters at levels as low as 0.2 pg 1-1. Several indirect determinations by AAS have been described. These included anionic detcrgents after complexing with ethylenediamine Cu(I1) (309, non-ionic surfactants using potassium tetrathiocyanatozincate (1 487) or phosphomolybdic acid in the presence of BaCl, (1 829, cyanate as the complex Cu(pyridine),(OCN),, and phosphate as ammonium phosphomolybdate (1 77’8).Reports on electrothermd atomization for water and effluent samples have been numerous and the applications data available to the water analyst is now much more satisfactory. Rains et crZ. ($84) compared the precision and accuracy of AAS using ETA withA pplicotions 155 that of other analytical techniques for 19 trace elements in natural waters.Rowely et al. (534) described a multi-element ETA-AA$ system and its application to the simultaneous determination of up to 6 elements in natural waters, each with individual background correction. The instrument used pulsed high-intensity HCL sources, a carbon rod atomizer and a self-scanned photodiode array spectrometer.Commercial graphite furnaces have been compared with the Woodriff furnace for determining Se in effluents (106). The latter was found to offer better sensitivity, detection limits and relative freedom from interferences. Epstein and Zander (1545) compared the determination of Ba in sea water using ETA with AES and background-corrected AAS.They concluded that ETA-AES was simpler and gave better precision. Kunert et al. (1566) found that the sensitivity of Hg determinations in the graphite furnace was considerably enhanced by the use of a Au or Ag foil liner. A comparison was also made with the cold-vapour technique. Thompson et d. (888) have described the batch preparation and use of La-coated graphite tubes for ETA of water samples.The tubes could be used for Cd, Mn, Pb and Zn, but not for Cu or Ni. A novel “thermal analysis” application of ETA apparatus was also described by these authors (96 I); evaporation and/or pyrolysis curves suitable for the characterization of a variety of organic compounds were obtained by monitoring absorbance in the furnace at 190.or 254 nm as a function of time or temperature. Identification and suppression of interferehces in ETA has continued as an area of considerable interest to the water analyst, and only a selection of the many reports can be mentioned here. In one report (2009), a range of methods of avoiding interference, e.g., furnace tube redesign, selective volatilization, matrix modification and standard additions, was used to determine Fe, Mn and Zn in sea water. Alternatively, other authors have attempted to keep determinations as fast and simple as possible.Thus, the direct ETA method for determining Cd in drinking water was compared with ETA after solvent extraction, with ETA using standard additions, and with ETA using matrix modification (116). Similarly, Weisel et al.(1227) found that in sea waters with identical major cation ratios, it was possible to determine Cd, Cu, Fe and Pb using pure standards simply by applying a correction calculated from the measured Na concentration. The determination of Pb in water continues to cause problems; Erspamer and Niemczyk (556) have investigated the mechanism of the MgC1, interference. It has been shown that when a rapid homogeniza- tion procedure for sewage sludges was used for sample preparation for ETA-AAS (see 4.6.l), the presence of high levels of conditioning agents, particularly inorganic additives such as A1 chlorohydrate (1444), caused interferences. The use of hydride generation techniques for elements such as As and Sr i s becoming increasingly common and several studies have been reported.A common trend i s now apparent, that is, a shift of emphasis from purely instrumental studies to finding chemical means of overcoming the inevitable interferences. Relevant references include 337 (effect oif As and Se on recoveries of each other), 450 (As in water), 698 (Sn in water) and 1794 (As and Se in sewage). Pyen and Fishman (478) described an automated system using NaBH, in which EDTA was mixed with the samples to minimize the interferences. Nakahara et a!.(1490) found that the Zn/SnCl,/KI system gave better selectivity for As than did the NaBH, system. Non-dispersive AFS was used to determine the As concentration. Reedrick and Gilbert (1 360) extended the scope of a Hg cold-vapour analyser to produce hydrides of As, Se and Sb, thus allowing simultaneous multi-element determinations of these elements by d.c.Ar plasma AES. 4.6.3 Atomic Emiss‘ion Methods Most reports in this area were concerned with simultaneous multi-element determinations, wherein lies the main advantage of AES over AAS. As might be expected greatest interest156 Analytical Atomic Spectroscopy has been shown in the ICP as an excitation source, but the use of the d.c.argon plasma for water analysis i s also growing steadily. Smythe and Finlayson (668) investigated several alternative techniques using four different instruments and concluded that ICP-AES has good potential for the determination of trace elements in natural waters. Kniseley (184) has described the application of FES and ICP-AES to continuous on-line monitoring of coal gasifier output streams: the main difficulty encountered was the design of a suitable transfer system.Modifications t o inductively coupled plmma sources of direct interest to this applica- tions area concerned mainly sample introduction. Ape1 et al. (515) modified the standard concentric nebulizer design so that up to 4000 water samples containing high salt levels could be run without clogging of the tip.It was also found (560) that traces of HF caused no deterioration in the glass needles of cross-flow nebulizers, which otherwise were constructed entirely from plastic. Greater effort is now being devoted to testing the accuracy ond reliability of ICP-AES techniques. Ward (584) has presented correlation data with AAS for CRMs and other water samples.Garbarino and Taylor (1063) found that precision and accuracy for routine water quality testing were equivalent to those obtained by AAS or colorimetric techniques, but frequently sensitivity was improved. Varnes (1 310) analysed three water standards issued by the U.S. Environmental Protection Agency for trace metals; elements with good sensitivity and low background (Be, Cd, Cr, Cu, Fe, Mn, V and Zn) gave excellent agree- ment, whereas metals with poor sensitivity and/or high background (Al, As, Co, Ni.Pb and Se) showed a slight positive error. The d.c. argon plasma has been the subject of several reports, each describing the use of the same commercial echelle spectrometer. None of these included the analysis of CRMs or accuracy comparisons with results by other techniques.Several groups, however, have investigated interference effects. Nygaard (1 53'9) found the two-electrode plasma unsuitable for trace heavy metals in salt water, but Hendrick and Eastwood (574), using the three- electrode plasma and a Li,CO, buffer for the same matrix, reported difficulties only with A1 determination, The three-electrode plasma was also found to be satisfactory for acid digests of marine sediments and organisms provided that note was taken of changes in background emission intensity (952).Table 4.6 WATERS, SEWAGE AND EFFLUENTS b 2 Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form As - Waters; environmental Trace levels As - Waters From 10 fig/l samples A G A G Hydride-evolution method Heated SiO, tube 258 8 337 rrr Adjust sample to pH 2-4, add NaBH, and carry As, Se hydrides to flame in stream of argon F Air/Ar/H, As - Drinking water Trace levels A L As 193.7 Aqueous wastes ng leveis (absolute) F G 197.2 Graphite furnace F Air/Ar/H, 348 412 Arsine generation method.Comparison of non--dispersive and dispersive fluorescence systems.(See also Hg, ref. 411) Treat with H C I/ K I /S n C IJZn . Hydride-generation method. Add HCI/KI, extract with benzene and back-extract into aqueous solution, t o determine inorganic As and methylated arsenical compounds Separate by co-precipitation with Fe(OH), and use hydride-generation method from HCI solution Extract with DDC/CHCI,. after addition of K I + ascorbic acid.Take 20-50 aliquot. After furnace drying stage, treat furnace with Ni(N0,),/H,02 solution (1 : 1) ,re-dry and proceed with ashing and atomization. (As, Sb) NaBH, hydride-generation method Hydride generation method L L 450 1130 As As - Waters 193.7 River water From 0.8 ng/ml ng/ml levels A A Graphite furnace As AS - Sea water - Waters 1.5 ng/ml level A A L Graphite furnace or heated cell 1132 L Graphite furnace 1150 As AS - Water - Waters From 12 ng (absolute) A From 1 ng/ml A Heated SiO, tube P D.c.argon plasma Graphite furnace 1232 1360 1366 As - Drinking water ng/ml levels A (A) Selectively extract As( Ill), Sb( I l l ) and Se( I V ) with APDC/MIBK (B) By prior reduction of separate sample, determine total As, Sb and Se as above, to obtain As(V), Sb(V) and Se(VI) by differenceTable 4.6 WATERS, SEWAGE AND EFFLUENTS- continued Element X/nm Matrix Concentration Tecil.Analyte Form Sample treatment Atomization Ref. As - Waste waters - F As - Natural waters ng/ml levels A As - Sea water - A As AS Au B Ba Be - Sewage effluents - Natural waters - Industrial effluents 249.7 Natural waters 553.6 Sea water 313.0 Stream sediments - A From 0.2 ng/ml A From 30 ng/ml A 0.14-1-1 pg/ml A Trace levels A, E 0.2-100 pg/g E Ca - Industrial effluents 1-lo00 pg/ml E A Ca - Waters and sewage - effluents Ca 422.6 Waters, geochemical Up to 200 ,Jml E fluids and brines L L, G G G L L L L S L L c Non-dispersive AFS system, with hydride- F generation method.Use of Zn/SnCI,/KI preferred to NaBH, ASH,-generation method Graphite furnace Co-precipitate with Fe(OH), at pH 8-9.Separate by flotation, using Na oleate, and dissolve in 5M HCI. Add KI and reduce with NaBH, Hydride-generation method, from 0 . N HCI solution Automated dual-channel instrument, for F - As and Se Adjust to pH 6 and pass known volume F Air/C,H, through Dowex 2-X8 column (treated with 3M HCI). Elute with 75% NH,OH Add 1 ml Ba(OH), solution (1% Ba) t o Graphite furnace 10 ml flask and dilute to volume with H,O (HGA-2100) sample.Take 5 aliquots Add KCI to all solutions. Ash at 1400 "C. Graphite furnace (Comparison of furnace AAS and AES (HGA-2100) modes) Dry, grind (300 mesh) and mix (1 : 2) A with buffer of SiO, + graphite (1 : 1). Monitor V 327.6 nm to correct for V interference on Be. Prepare standards in synthetic sediment matrix Air/Ar/H, Heated cell Heated cell 17 A d.c.- F - Dilute ( x 10) and add La to a level of 1000 pg/ml in final volume (12 pp. booklet) determination of Ca, K, Li, Na over wide range of concentrations F Air/C,H, Simplified (2-standard) method for F - 1490 1536 1767 1794 1930 229 502 1545 566 398 1426 1465Cd - Drinking waters ng/ml levels A Cd - River waters, sediments Trace levels Cd Cd Cd Cd Cd Cd - Drinking water Trace levels - Offshore waters, sediments, - marine organisms - Sea water Trace levels - Non-saline waters - A A - A A 228-8 Sea-water particulates 228.8 Sea-water sediments 2-30 pg/g A (on dry weight) Trace levels A Cd - Sea water ng/l levels A Cd 228.8 Sea water, mussels - A Cd - Sea water Cd - Sea water Cd - Sea water Cd - Drinking water Cd - Sea water Trace levels A L L L - L L L L L L L L L L L Four approaches evaluated : (A) Direct method (B) Standard addition method (C) APDC/MIBK extraction (D) Matrix modification Extract waters with DDC/MIBK.Digest F - sediments with acid Graphite furnace - Review Graphite furnace - - Evaluation of releasing agents used to overcome chemical and matrix interferences Graphite furnace Investigation of La-coated graphite tubes.Graphite furnace Recommended method : Batch treat n on-pyroli t ic a1 ly coated tubes by immersion in warm 50% La(NO,),.6 H,O solution, under reduced pressure Filter through 0.45 pm Nucleopore filter and digest residue ( x 2) with 5N HNO, at 90 "C i n closed PTFE vessel Dry at 100 "C, agitate ultrasonically i n acetone and separate into density fractions in tetrabromoethane/acetone mixture (5 levels).Dissolve separate fractions in HF/HNO,/HCIO, Description of sampling and chelation- extraction procedure for Cd, Cu, Ni, Zn Add HNO,, reflux, buffer to pH5 with NaOH/Na citrate and extract with dithizone/MlBK Graphite furnace F Air/C,H, Graphite furnace (HGA-74) Graphite furnace F Air/qH2 Graphite furnace Modified standard addition method, using Graphite furnace corrections based on Na concentration Separate on Chelex 100 resin Graphite furnace Add ascorbic acid Application of Pt-loop device Graphite furnace F - Acidify with HNO, and add 1000 pg/ml Graphite furnace La (NO, 1, ( HGA-2100) 116 e 2 -. 306 348 669 730 888 953 1030 1070 1203 1227 1516 1630 1684 1750d Table 4.6 WATERS, SEWAGE AND EFF'LUENTS- coiztirtued h 0 E(ement X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form Cd - Sea water - Cr 357-9 Sewage sludge - A A Cr - Sea water - A Cr - Drinking water Trace levels A Cr 357.9 Waters, sewage, effluents Trace levels A Cr Cr Cr c s c u Sea water 357.9 Waste waters - Water - Water - Waters 0-5 pg/ml (in extract) Trace levels ng/ml levels A A A A A L L L L L L L L L L Application of Zeeman-effect AA - - Homogenize and digest under pressure with HNO,.Results are compared with those of method using FAAS+HNO,/H,SO, digest ion Study of Cr speciation i n sea water, via controlled electrodeposition on graphite tubes I Graphite furnace Add 4 ml 25% HCI solution + 2 rnl lCr% NH,CIO, solution to 50 ml sample, evaporate to 20 rnl, add 0.5 m l H,O, and evaporate to 5 rnl.Dilute Electrodeposit Cr on pyrolytic coated graphite tube electrode, at pH 4-7, i n flow-through cell. Variation of potential allows Cr(ll1)-Cr(VI) species to be distinguished Extract C r ( l l l ) oxine complex with F Air/C,H, MlBK at pH 7.24.2 Extract with APDC/MIBK, after sample treatment with PHP-buffer (pH 4.7-5.5; 60 "C; 20 rnin reaction time), t o remove C r ( l l l ) and Cr(VI) simultaneously Pass through NH,-hexacyanocobalt ferrate Graphite furnace (NCFC) exchange column t o trap Cs and recover by dissolution of NCFC ,in hot 12M H,SO,.Dilute to volume. (Discussion of interferences given) Add chelating resin (< 400 mesh) to sample, stir for 30 min, filter, wash and suspend resin -t Cu i n small volume of H,O.Take 10 aliquot, dry at 350 "C, ash at 1400 "C and atomize at 2700 "C Graphite furnace Graphite furnace F Air/C,H, Graphite furnace Graphite furnace (HGA-76) Graphite furnace 2060 12 195 340 509 1192 1276 $ $ 2023 a, Y, 5' 919 9 3 -. 172 3 $ 2 0 'nc u - Waters c u - Waters Trace levels Trace levels c u c u c u c u c u c u c u c u Fe Fe - Sea water 324-7 Natural waters - Sea-water particulates - Sea water - Sea water - Natural waters - Sea water - Sea water - Sea water 248.3 Sea water 253.7 Fresh and sea waters - Waters, effluents Hg - Waters; environmental H!a - Waters samples 0.02-500 pg/l 50 pg/g-l YO (on dry weight) ng/l levels Trace levels Trace levels 0.42-0.88 ng/ml - Trace levels From 0.2 ng/ml ng/ml levels Trace levels Trace levels 0.1 ng/l levels A A A A A A A A A A A A A A A E L L L L L L L L L L L L G G G L Load polyurethane-foam plug with F Air/C,H, 1-(2-pyridylaz0)-2-naphthol, immerse i n sample and subject to regulated squeezing sequence.Dry, extract with CHCI, and back-extract with H,O/HCI for Cu, Zn by AAS Comparison of ETA-AAS and GC 4- flame F lonisation detector methods for detection Graphite furnace of or g ano-met a I I ic corn p oun d s of Cu , Hg and Sn - Extract Cu, Mn with DDC/CCI,.Evaporate F and redissolve i n HCI. (Comparison with NAA method) Air/C,H, Evaporate 1 I sample with 250 mg F Air/C,H, charcoal and extract with HNO, See Cd, ref. 953 Graphite furnace See Cd, ref. 1070 Graphite furnace See Cd, ref. 1227 Graphite furnace Extract Cu, Pb, Zn with dithizone/CHC13 and back-extract into aqueous medium Graphite furnace Graphite furnace Extract with dithizone/CCl, Separate and concentrate Cu, Pb, Zn on F Air/C,H, column.Elute with I M HCI See Cd, ref. 1227 Graphite furnace Graphite furnace (HGA-2200) Adjust to pH 1 .O with HNO,, irradiate with U.V. light and add SnCI,. (Study of effect of presence of humic malerial) Cold vapour Digest on water-bath with excess KMnO,, Cold vapour K2S,0, and HNO,.Proceed by standard cold vapour method ( 2 alternative treatments compared} See also As, Se, ref. 258 Cold vapour Y 293 2 h -. 2. - 4 449 498 721 953 1070 1227 1537 1797 2031 1227 2009 8 38 258 289 ;;;Table 4.6 WATERS, SEWAGE AND EFFLUENTS-cmtirtued Element h/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form HQ Aqueous wastes ng levels (absolute) - Waters Trace levels 253.7 Waters, sewage, effluents 0-10 @g/l 253.7 Sea water 0-100 ng/1 253.7 253.7 Waters, sediments From 0.02 ELg/I Waters, effluents, sludges - Waters, effluents, sludges - Sea water - Waters, sediments 0-400 ng (absolute) Waters - Waters - Waters 0.008-1 $J/l Waters - Waters 0.75 ILg/l level F A A A A A A A A A - A A A G L L L.G L, G - - G G G - G G G Reduce with SnCI, and transport Hg vapour i n argon stream. (Comparison of dispersive and non-dispersive fluorescence systems) See Cu, ref. 449 Acidify to 2.5M with HCI, irradiate with U.V. light (10 min) and reduce with SnCI, Acidify to 0.2M with H2S0,, stand for 20 days, reduce with SnCI,, collect Hg on Ag wool and heat to 500 "C.(Study of Hg storage losses. Glass vessels recommended) Treat with acid dichromate solution, followed by U.V. treatment and reduce with SnCI, Two methods are proposed : (A) For non-saline waters, effluents and sludges. (Total Hg) (6) For saline waters. (Inorganic Hg + organo-Hg compounds forming dithizonates) Cold vapour - - Cold vapour Cold vapour Cold vapour (30 cm cell) - - - - - Reduce with SnCI, Cold vapour Reduce with SnCI, Cold vapour Contamination study Cold vapour Apply preliminary U.V.oxidation A - Reduce with NH,OH.HCI SSnCI, Cold vapour Reduce with SnCI, and collect Hg on Ag Cold vapour wool, prior to release by heating Inter-laboratory investigation of two Cold vapour methods : (A) Oxidation with HNO,/H,SOJKMnO,/ (6) U.V.irradiation i n presence of Kp,O, + H,SO, or HNO, K A O , 41 1 449 470 477 496 1076 1224 1404 $ 1446 $. 1512 4, 1566 ,b 1614 1478 3 3 2 2 B 5. 1719 0 'c,Hg Hg K K K LI LI Lt Mg Mn Mn Mo N Na Na Na NI N1 P (PO,) - 253.7 - - 769.9 - 670.7 610.3 670.7 - - 279-5 313.3 - - - 589.0 232.0 - - (Mo) Waste waters pg/ml levels Water Gasifier effluent River water Waters, geochemical fluids and brines Industrial effluents Stream sediments Waters, geochemical fluids, brines Boiler feed waters Sea water Sea water Sea water Water Gasifier effluent River waters Waters, geochemical fluids, brines Sewage sludge Sea water Sea-water sediments 0.1 pg/ml level ng/g levels From 0.08 pg/ml up to 0.1% - 0.5-500 pg/g up to O-O!wo 0.01-2 pg/ml 0-5.20 ng/rnl From 0-2 ng/ml 0.1-4 ng (absolute) ng/g levels From 0.05 pg/ml up to 0.1% - ng/l levels - A E E E E E E E F A A A E E E E A A A G L G L L L S L L 1.L L L G L L L L L (A) Precipitate with N a p (€3) Reduce with Zn dust Take 1 ml sample into discharge vessel P R.f. "ring" and remove H,O at 0.1 Torr, -30 "C. Excite dry residue in r.f. inductively- coupled ring discharge Cold vapour discharge - F - - P - P ICP See Ca, ref. 1465 F - - F - See Be, ref. 566. Use Li 670.7 nm for Li below 10 pg/g, otherwise Li 610-3 nm A 17 A d.c. See Ca, ref. 1465 F - I w Automated on-line non-dispersive AFS system See Cu, ref. 498 Add MgCI, as interference suppressant Improvements to earlier OES/isotope- dilution method (see WRC Information, 1977, 4, Abslr. No. 254) See Ca, ref. 1465 F Air/propane F Air/C,H, Graphite furnace Graphite furnace (HGA-2200) (HGA-2100) - - P - P ICP F - F - See Cr, ref. 12 See Cd, ref. 1070 Extract with HNO, (1 : l ) , add molybdic F - acid solution and extract complex for Mo determination Graphite furnace Graphite furnace 1793 2 3 1829 5- h 184 1209 1465 398 566 1465 938 498 2089 1488 666 184 1209 1465 12 1070 1778 c chI Table 4.6 WATERS, SEWAGE AND EFFLUENTS - continued 0 P Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Drinking water Waters Waters Natural waters Sea water Non-saline waters Sea-water particulates Waters Boron-containing waters Sea water Sea water Water Industrial waste waters Natural waters Waters, sediments, fish Drinking water Sea water Sea water Trace levels A cLg/l levels A Trace levels 0.02-1000 pg/I Trace levels - 1 lMQ0 ps/s (on dry weight) - Trace levels A - F Trace levels A Trace levels A A - A - 39-1 300 pg/m I A A - L L L L L L L L L L L L L L G L L L - Graphite furnace Digest with 5% HCI and use 25 @ I Graphite furnace aliquots.Addition of 100 mg/l Mo solution to samples and standards reduces some interferences.Dry at 100 "C, ash at 700 "C and atomize at 2100 "C Study of MgCI, interference Graphite furnace See Cu, ref. 721 See Cd, ref. 730 F Air/C,H, Graphite furnace See Cd, ref. 888 See Cd, ref. 953 Graphite furnace Graphite furnace Review of AAS methods F Air/C,H, Graphite furnace Study of interference by 500-1500 pg/ml F - levels of B on Pb atomic emission P D.c.plasma Acidify and electrolyse at 3-2-5.2 V using W wire electrode. Heat wire in furnace for analysis See Cd, ref. 1227 Graphite furnace Graphite furnace Extract with TOPO/MIBK from HCI/ F Air/C,H, ascorbic acid/KI medium See Cu, ref. 1537 tetra-alkyl lead compounds by GC prior t o AAS measurement Extract with dithizone/CHCI, and Graphite furnace back-extract with 0.1M HCI. Add 212Pb t o (FLA-100) allow correction for extraction yield Graphite furnace Extract with hexane and separate - - See Cd, ref. 1684 F - See Cd, ref. 1750 Graphite furnace (HGA-2100) 348 51 9 556 72 1 730 888 953 1026 1078 1193 1227 1453 p 1525 x ij- 1537 1641 b $ 1684 '' 1704 B ';. 1750 2 bPb Pb Pb Pb Pt S Sb Sb Sb Se Se Se Se Se Se Se Se Se - Sea water - Sea-water sediments 217.0 Waters - Sea water - Industrial effluents 384 Water - Water - Water (S, band) - Drinking water - Effluents - Waters; environmental - Waters - Drinking water - Waters - Waters samples - Drinking waters - Natural waters - Natural waters - A From 0.2 ,&g A ng/ml levels A A - From 0.04 pg/ml A 5 ng level E (absolute, as sulphate) A - From 1 ng/ml A ng/ml levels A 100 pg level A (absolute) Trace levels A From 1 pg/l A Trace levels A From 3 ng (absolute) A From 2 ng/ml A ng/ml levels A ng/ml levels A ng/l levels A L L L L L L L G L L G G L G G L C, G L G C/AAS met hod, t o investigate F - TEL/sea-water interaction (A) Organic Pb compounds- Extract by Graphite furnace vacuum distillation and condensation in liquid-N, trap.Extract condensate with C,H, dried sediment with HCI/HNOJHGIO,, evaporate and redissolve in H N O,/H,P 0, (B) inorganic Pb compounds-Digest Add thiourea Graphite furnace (+ Mo tube) See Cu, ref. 2031 See Au, ref. 229 F Air/C,H, Mix sample with Sn/H,PO, reagent at F NJH, 180-220 "C (MECA application) See As, ref. 1150 Graphite furnace Graphite furnace See As, ref. 1360 See As, ref. 1366 Comparison of graphite cup and Woodriff furnace methods See As, ref. 258 Graphite furnace Graphite furnace Heated SiO, tube See As, ref. 337 F Air/Ar/H, - Graphite furnace See As, ref. 1232 Heated SiO, tube See As, ref. 1360 P D.c. argon plasma See As. ref. 1366 Comparison of ETA-AAS and hydride-generation methods Extract with APDCJCHCI, and back-extract into aqueous medium Graphite furnace Graphite furnace Graphite furnace A 1796 2 7 $ 1920 2. 201 8 2031 229 580 1 I50 1360 1366 106 258 . 337 348 1232 1360 1366 1391 1538 -c m Table 4.6 WATERS, SEWAGE AND EFFLUENTS- continued Form Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Se 196.0 Water 0.05 ng/ml level A L Acidify 1000 ml sample, add 2 ml Fe( I l l ) F N,/H, 1705 solution and precipitate Fe(OH), with NH,OH.Add Na lauryl sulphate solution, transfer to flotation-separation cell and dissolve precipitate in HCI. Reduce with NaBH, t o generate H,Se ( + SiO, cell) Se Se si Sn Sn Sn Sn Sn Sn Sn - Sewage effluents - A G Use 3N HCI solution. See As, ref. 1794 Heated cell 1794 - Natural waters From 0.2 ng/ml A L See As, ref. 1930 F - 1930 251 -6 Industrial process waters 2.5-180 ng/ml A L Add Ca and La.Atomize at 2600 "C Graphite furnace 1703 (HGA-2200) - Waters 286.3 Waters Trace levels A L See Cu, ref. 449 - I 449 0-20 pg/l A L Add EDTA and reduce with NaBH, t o Heated tube 478 generate SnH, evolution (850 'C) 224.6 River and lake waters From 0.1 g A L, G Dilute sample (containing < 10 pg Sn) F Ar/H, 698 (absotutef to 90 ml with H,O, adjust to pH 2.5 with H,SO, and dilute t o 100 ml.Take 20 ml aliquot, add 1-4 rnl of 1% HCI + 1 g N%SO,, mix, add 7 ml 40% KCl solution and reduce by addition of NaBH, pellet. Sweep SnH, in argon flow 286.3 Industrial waste waters Trace levels A L See Pb, ref. 1525 F N,0/C,H2 1525 Te 224.6 Waste waters and 0-150 ng/l A L For interference suppression, add 20 Graphite furnace 1583 286.3 Waters, sediments 0-5 pg/g level A L Hydride-generation method, for Sn( I V ) F Air/H, 1711 - Waters ng/ml levels A G Co-precipitate with FeCI, at pH 4.0, Heated cell 1813 f?.sediments 10% ascorbic acid to 20 sample (HGA-2100) and speciation of organo-tin compounds separate by flotation, using Na dodecyl sulphate and dissolve in 6M HCI. Reduce to hydride with NaBH, ( + SiO, tube) 2. 2 $ s. s 2 2 214.3 River water.sea water 2 4 0 ng/ml A L (A) For Te( IV), add EDTA and acetate Graphite furnace 1477 Q buffer solution (pH 5.5) and extract with DDCjMlBK HCI solution, add EDTA, neutralize with NH,OH, buffer t o pH 5-8, and extract as before (B) For Te(lV) + Te(VI), prepare 4M 0TI Zn Zn Zn Zn Zn Zn Zn Zn Zn Anionic detergents Organo- silicon compounds Organic species Surf- actants Cyanate (indirect) - Natural waters 213.9 Sewage sludge - Waters 213.9 Natural waters - Sea water - Sea-water particulates - Sea water - Natural waters 213-9 Sea water Trace levels - Trace levels 0.02-200 @g/l 4 b m m pg/g Trace levels (on dry weight) ng/l levels Trace levels From 0-4 ng/ml - Sea water 324-7 Waters (Cu) 251 -6 Effluents - Natural waters 213.9 Waters (Zn) 324.7 Effluents (CU) - @g/rnl levels Up to 0.1 mg/ml ( i n extract) Various levels 0.052 @g/ml 1-100 pg/ml (as OCN) A A 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 L Separate TI by anion-exchange F - See Cr, ref. 12 Graphite furnace F Air/C,H, See Cu, ref. 293 See Cu, ref. 721 F Air/C,H, See Cd, ref. 730 Graphite furnace See Cd, ref. 953 Graphite furnace See Cd, ref. 1070 Graphite furnace See Cu, ref. 1537 Graphite furnace Mix sample (1 : 1) with NH,NO, solution Graphite furnace (10 mg/ml) (HGA-2200) See Cu, ref. 2031 Graphite furnace Add ethylenediamine-Cu( I I ) complex to water at pH 6-9. Extract detergent complex into CHCI, and analyse for Cu Graphite furnace (HGA-2200) To determine methylsiloxane compounds, F separate from inorganic silicates by extraction with pentanol/MIBK (1 : 1) at pH 5-7.Standardize with solutions of tetramet hyldisi loxane-1 ,3-diol N,O/C,H, Extract sample with solvent, inject into furnace and heat slowly, in nitrogen atmosphere to 1000 "C. Record trace of absorbance vs. time at 190 nm and 254 nm, to characterize various pollutant- type organics, e.g., oils, greases, tars, etc. Graphite furnace (CRA-90) Adjust to pH 68, add Zn(SCN), reagent F Air/C,H, + 1,2-dichlorobenzene and shake. Back-extract with 0.7M HCI and measure Zn To 50 ml sample add 10 mi 0.138M Cu solution (170 m l pyridine +34-5 g CuS0,.5H20 diluted to 1000 ml with H,O) and dilute to 100 mi.Extract with 10 ml MlBK F Air/C,H, 1074 12 5 d 293 2 721 2 730 953 1070 1537 2009 2031 305 777 961 1487 1612 r-- OITable 4.6 WATERS, SEWAGE AND EJ?l?LUENTS-ccontinued c rn Element h/nm Matrix Concentration Tech- Ana’yte Form ~~ ~ Sa.mple treatment Atomization Ret.Non-ionic detergents Various (13) Various Various (11) Various (9) Various Various Various Various Various Various Various Various (6) Various (9) (9) 313.3 Waters, sewage From 0.02 pg/ml A (Mo) Effluents (paper industry) ng/ml levels A Stream waters Trace levels A (0.2-10 ng/ml) Waters Trace levels - Fresh waters Trace levels A Surface and waste waters Drinking waters Sea water Marine sediments Plant effluents Waters Natural waters Sea water ng/ml levels - Trace levels A - A Trace levels E Trace levels - - - E Trace levels A - A Waters, effluents - L L L - L - L L L - - L L L Extract with ethyl acetate, evaporate t o F Air/G,H, dryness, add solution of BaCI, + phosphomolybdic acid, dilute, shake and filter.Determine Mo in filtrate Review of procedures for the elements As, Sb, Be, Cd, Cr, Cu, Pb, Ni, Se, Ag, Zn, TI and Hg Add HNO, and digest in furnace to decrease non-atomic absorption effects. Atomize at 2600 “C Study of trace metal levels in H,O/HNO, - - samples stored for 4 years i n linear- polyethylene containers Stabilize samples by addition of 0.5 g/I F - ascorbic acid, at pH 2.5, and pass through Amberlite I R-120 cation-exchange column, to concentrate Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb Study of methods for speciation of trace - - metals Detailed study of factors affecting Graphite furnace Graphite furnace Graphite furnace APDC/MIBK extraction method (HGA-2100) Concentrate trace impurities by F - co-precipitation and flotation Cu, Ni, Fe, Cr, Zn, Cd, Pb, V and Co Extract with HNO,, to determine P ICP Review of techniques - - Review of monitoring programmes and - - instrumentation Multi-element DR method P ICP Concentrate by Chelex-100 treatment and Graphite furnace elute Cd, Co, Cu, Mo, Pb and Zn with 2N HNO,, 1N HCI and 4N NH,OH Automated system F - 1828 7 9 11 37 88 117 204 5 219 $ E x 212 :- a, 220 5 221 t, 281 ’ -.s 2Various - (15) Waters E Various - Mineral waters (10) Varlous - Natural waters (6) Various - Water (7) Various - Natural waters Various - Sea water (8) Various - Snow (12) Varlous - Waters (19) Various - Waters (12) Trace levels ng/rnl levels Trace levels Trace levels ng/ml levels ng/g levels A A A A A A pg/rnl and E ng/ml levels Minor and trace levels E Evaporate bulk sample to dryness and A 7.5 A d.c. mix residue (1 : 1 : 2) with Li,CO, buffer and graphite powder containing In and Pd as internal standards.Base standards on synthetic matrix of Mg0-CaOSi0,-AI,O, Pass sample at controlled rate through F - ANKB-2 arnpholyte (H+) column and elute trace elements with 2M HCIO,.Evaporate to dryness and redissolve for AAS determination of Cr, Mn, Co, Ni, Cu, Zn, Li, Sr, B, ( F ) Co-precipitate impurities at pH 8 as F - carbonate and dissolve in HCI, to determine Fe, Pb (> 5 ng/mI) and Cd, Cu, Mn, Zn (> 2 ng/ml) Add H,SO, to prevent Ca interference on Graphite furnace Be. For Cd, correct for Na interference by measuring absorbance at 228-8 nm and 226.5 nm.Results quoted for Be, Sb, Mo, V, Co, Ni, Cd Study of wire-loop atomizers vs. furnace systems Adjust to PH 5.0-5.5 and pass through Chelex 100 resin column. Elute with NH, acetate to remove alkaline elements and with HNO, to determine Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn Concentrate 1000 ml sample to approx. Graphite furnace 10 rnl by non-boiling evaporation (70 "C) (HGA-70) in PTFE vessel.Determine Al on aliquot of this concentrate. Add HF + HNO,, evaporate to near-dryness and dissolve i n H,O for determination of Na, Mg, K, Ca, Fe, Mn, Pb, Cd, Cu, Ag, Zn - P D.c. argon - P ICP (10 : 5 : 4 : 1) Flameless systems Graphite furnace (HGA-2100) plasma 295 .o" ", 9 -. .-.. 0 h .-I 330 363 447 448 456 465 514 515 LTable 4.6 WATERS, SEWAGE AND EFFLUENTS- continued c 8 Element X/nm Matrix Concentration Tech. Sample treatment Atomfzatfon Ref.Form Various Various (7) Various Various Various (28) Various Various Various (6) Various (15) Various Various Various (15) ( 8 ) Various Various (20) Various (19) Waters Marine sediments Stream sediments Waters Waters Waste waters Waters Fresh and sea water Natural waters Water Water Sea water Sea water Waste waters Natural waters Trace levels A Trace levels A - E E Trace levels E - 5R120 ng/ml E - A - - Trace levels E, A 1-1 0 p / l - Trace levels - Trace levels E Trace levels A Various levels E 1-200 ng/rnl A (various elements) L L L L G L L - L - - L L S L Multi-element system (up to 6), using self-scanned linear photodiode array spectrometer Leach with 5N HNO,.Results for Cr, Fe, F - Ni, Cu, Zn, Cd, Pb compared with those of PlXE method Extract with HF/HNO, (1 : l ) , evaporate P ICP lo dryness and redissolve in HNO, Review P ICP Method for detection of halogen- P MIP (He) containing organic species in waters, using GC detector - P ICP Graphite furnace Review F - Study of chemical state of heavy metals - - (Cd, Cr, Cu, Ni, Pb, Zn) in waters Review of atomic spectroscopic methods F, P - and study of sample concentration procedures Review of sample concentration methods - - Review of sample filtration devices Description of ICP/echelle spectrometer P ICP system for up to 20 elements.lon- exchange method of pre-concentration given for Fe, Cu, Ni, Zn, Co, Cd, Pb, Mn Study of direct method Evaporate 1 ml sample with 20 mg A 10A graphite powder and add NaCl to residue to give 0.5% Na content.Excite mixture in cratered graphite electrode - Graphite furnace - - Graphite furnace 534 544 560 584 608 640 662 664 668 670 671 $ 731 ?’ % 5 732 s 743 0 h -. x 3 8 8 4 2 0. Various Various Various Various Various (11) ( 8 ) Var i oua Various (7) Various (17) Various ( 6) Natural waters Sea water, sediments, marine organisms Natural waters Trace levels Trace levels Trace levels Trace levels Trace levels E E - E A A, E A E A - - A L L - L L L L L L - - L L L L Review P ICP Buffer with high-purity Li,CO, P D.c.plasma 4 .- 951 % 952 5 i5 =. 954 9 F XRF method, but with details of new - - chelating cellulose filter system For sea-water samples, match standards P D.c. plasma to sample matrix Treat with HNOJHCIO, and analyse F - digest for Cd, Co, Cu, Fe, Mn, Ni, Pb.Zn. (Marine pollution survey) Review F - Survey of drinking waters from 70 F - Canadian municipalities, for Cd, Cr, Cu, Pb, Zn, Ca, Mg - P ICP Waters 960 Sea water, sediments 998 Waste waters Drinking waters Trace levels Trace levels 1060 1061 Natural waters All levels 1063 1071 Sewage and effluents (A) Homogenize and analyse directly F - (6) Digest with acid (FAAS) (Comparison of methods, for Pb, Cu, Cd, Cr, Ni and Zn) (ETA-AAS) Graphite furnace Review (479 refs.) - - Book (1136 pp.) - - Filter acidified 3 I sample through F Air/GH2 membrane filter, adjust to pH 8.0-8.5, add 5-su Ip ho-8-q ui nolinol corn p lexing agent and adsorb on ion-exchange resin column.Elute with 2M HNO,.(Cu, Cd, Zn, Mn, Pb) - P ICP Various Various Various (5) - Estuarine samples - Waters - River waters Trace levels I ng/ml levels 1072 1073 1127 Various (10) (27) Various River waters, industrial wastes Waters ng/ml levels Trace levels E A 1131 1166 Preparation and analysis (by AAS, XRF F - and NAA methods) of multi-element standards Various Waters Trace levels A, E Review F - Graphite furnace P - 1205 c 4 c+ Table 4.6 WATERS, SEWAGE AND EFFLUENTS- continued 4 h, Element X/nm Matrix Concentration Tech.Sample treatment Atomlzatlon Ref. Form Various Various (101 Various Various Various Various Various (14) (4) Various (6) Various Various Various (11) Varlous (7) Various Waters All levels A, E L. G Waste waters Drinking water Waters, effluents Waters Drlnklng water Sewage effluents and sludges Sewage sludges Waters Sewage effluents and sludges Waters, effluents Sea water Sewage sludges Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels - - ng/ml levels ng/ml levels - A A E E E A A - A A A A L L L L L L L - L L L L Review F - Graphite furnace P - - F - Study of heavy metal distributions - P ICP Investigation of trace element P ICP pre-concentration by treatment with a polydithiocarbamate resin - P ICP F - Acidify to 1 YO ( V / V ) with HNO, and alternative t o digestion methods.Take 20 (A) Digest with HNO,/H,O, Results given for Cd, Cr, Cu, Ni, Pb, Zn. See also ref. 1442 Survey of inter-laboratory (16) results. - - (Na, K, Ca, Mg, chloride, sulphate, fluoride) Review of AAS methods for heavy metals F - Graphite furnace homogenize (5 min, 8000 rpm), as (HGA-76) aliquots t o determine Al, Ca, Fe, Mg Graphite furnace (B) Homogenize (HGA-76) Dissolve (oxidizing conditions) and F - extract metals with APDC into 2,6-dimethyl-4-heptanone (V, Cr, Mn. Fe, Co, Ni, Cu, Zn, Mo.Cd, Pb) Adjust to pH 8, extract metals with dithizone/CHC13 and back-extract into 2M HCI (Ag, Cd, Zn, Pb, Co, Cu, Ni) None, other than homogenization.(Comparison of ETA-AAS with FAAS and colorimetric methods) F - Graphite furnace 1206 1240 1241 1271 1309 1310 1442 1444 1452 b e 1454 ;i' 1467 ' b s 3 2. 1500 c/l x 1501 5 0Various - Waters Trace levels - (5) Various - Effluents Trace levels E Various - Waters Trace levels A A Various - Sea water - Various - Sea water Trace levels E (6) Various - Lake waters, sediments Trace levels A (14) Various - Sewage sludges ( 6) Various - Waste waters Various - Sewage sludges (9) Trace levels A 0.05-20 @g//ml E pg/ml levels A Varlous Varlous (13) Various (7) Various (6) Various (9) A - Sea water; marine - - Waters, snow Trace levels A organisms - Sea-water sediments Minor and A - River waters Trace levels A trace levels - Drinking water Trace levels A - L L L L L L, s L L L L L L L Review of methods for Pb, Cd, Cu, Ni.Hg- - - P ICP - F - - Graphite furnace Separate on Chelex 100 resin column P D.c. arc (Cd, Cr, Cu, Pb. Ni, Zn) Sample in high-density polyethylene F - containers, adjust to pH 7, and add small volume of buffered NaDDC solution. Extract for analysis with CHCI,, evaporate to dryness in presence of HNO, and redissolve i n 10% HNO,. For sediments, dry, sieve, digest with HNO,, followed by HCIO,, filter, evaporate and redissolve i n plasma icwO HNO, Comparison of treatments prior t o F - determination of Cd, Cu, Cr, Ni, Pb, Zn : Graphite furnace ( 8 ) Digest with HNO,/H,SO, (C) Digest with HNO,/HIO, (D) Ash and redissolve Pulse-injection system. (Elements : P ICP B, Ba, Cd, Cu, Fe, Mn, Mo. Ni, Zn) Dilute ( x 50) after homogenization and F N,O/qH, acidify with HNO, (for Al) (A) Prepare homogenized slurry (HGA-72) Graphite furnace Description of acid-digestion sample rack Graphite furnace (HGA-76) Filter sample (0-1-6 I; pH 3-6) through metal sulphide layer (ZnS, MnS, CuS or PbS), dry and extract with HCI/HNO, (for Pb, Cu, Ni, Zn, Cr, Fe, Mn) Extract with APDC/MIBK (for Cd, Co, F Air/C,H, Extract with APDC/MIBK (for Ag, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb) Graphite furnace Treat with H F/HCI/H NO, F - Gu, N i , Pb, Zn) Graphite furnace 1503 1508 ’* 1517 o 1522 1539 1557 g 2. 1568 1572 1588 1611 1615 1756 1758 I 1759 -1Table 4.6 WATERS, SEWAGE AND EFFLUENTS-conrinued Element X/nm Matrix Concentration Tech. Analyte Form Sample treatment Atomization Ref. Various Various (7) ( 8 ) Various Various Various (12) Various (14) Various Various (6) Various Various ( 8 ) (6) Various Various (131 (18) Stream sediments Natural waters Waters, environmental samples Waters Antarctic snows Hot spring deposits Raw sewage, effluents Sea water Waters Drinking water Lake waters River and estuarine sed i rnents Trace levels Trace levels Trace levels Trace levels Trace levels Various levels Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels A A E - A A, E A A A A A A L L L - L L L L L L L L Study of ashing effects on determination F - 1783 of Go, Fe, Mn, Pb, Zn, Cu, Ni Study of DDC/di-isobutyl ketone F - 1798 extraction method, for Cu, Cd, Pb, Zn, Mn, Co, Ni, Fe Prepare solution ,in HNO,/HCIO, or P ICP 1847 H F/H NO,/H C 10, med iurn Review of methods - - 1858 - Graphite furnace 1885 F - 1923 P D.c. arc F - 1929 plasma Separate heavy metals (Cu, Pb, Ni, Zn, Graphite furnace 1954 Cd, Co) on Chelex lLYU-(calcium form) column. Elute with 0.01M HNO, for Zn, Cd, Co, Ni and then 1M HNO, for Cu, Pb Elements : Ag, Cd, Cr, Cu, Fe, Mn, Pb, Zn Wire loop (W/Re) 2010 Comparison of two methods : Graphite furnace 2022 (A) Direct (B) ATMDTC/MIBK extractim (Elements : Cd, Cu, Pb, Zn, Cr, Ba) - Graphite furnace 2026 - F - 2029 (CRA-63) (HGA-76) Graphite furnace

ISSN:0306-1353    

DOI:10.1039/AA9790900152

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

A pplicatioiis 155 4.7 SOILS, PLANTS AND FERTILIZERS Scrutiny of the work reported in 1979 dealing with the application of analytical atomlc spcctrometry to soils, plants and fertilizers might lead to the conclusion that the decade closed with a period of stagnation rather than a phase of steady development. Such a conclusion would be unjust, because the benefits of the extensive efforts of manufacturers to improve instrument performance and to facilitate the optimized operation of spectro- meters are undoubtedly being felt in this area of analysis as in others.Howcver, on paper at least, the year is seen merely as a further period of consolidation of tried and tested techniques, with only minor modifications as required by samples or elements that present particular difficulties to the analyst.Two relevant reviews of the application of flame spectrometry have been published (1905, 19M) One, by David (1 %4), described analytical procedures for the determination of exchangeable cations, total amounts of elements in soils, and a range of trace elements in soil extracts. The other was concerned with thc application of AAS to the study of heavy metal pollution of soils (190’5).Automated sample processing and introduction is attractive as an approach to incrcas- ing sample throughput in laboratories that do not quite need (or cannot afford) more sophisticated multi-element determination systems such as direct reading OES. Kane and Hambleton (1431) described an automated system for the determination of K in fertilizers, based on the official AOAC method, which incorporated Li as an internal standard to eliminate the effects of phosphate.A linear working graph was obtained, and noise and drift were reduced. Other authors described a procedure for the determination of Ca and Mg by AAS and K by FES in plant digests, which exploited the advantages of flow injec- tion analysis (495). The sample was injected into a continuous stream of water flowing into the nebulizer.Cooksey and Barnett (47’1) described the applicability of a Perkin-Elmer model 5000 AA spectrometer to automatic sequential determinations in soil extracts and plant digests. For the soil extracts, 50 samples could be analysed for Ca and Mg by FAAS and K and Na by FF.S in 25min, excluding sample preparation time.For plant samples, Ca, Cu, Fe, K, Mg, Mn and Zn could be determined at a rate of one sample per min. Certified reference materials are invaluable in evaluations of analytical methods. A Japanese group (1934) have evaluated pepper-bush leaves (clethrcr barbinervis) as a CRM. They found the plant material to be quite homogeneous and to contain high levels of Co, Cu, Mn and Zn, which made it especially suitable for the assay of plant materials high in these elements. 4.7.1 Sample Preparation The use of a singEe wet digestioit for the determination of several major nutrient elements in plant samples is potentially very attractive. It has been shown that a simple and rapid digestion procedure based upon pre-digestion with concentrated H,SO, and a final brief digestion with HC10, in H,SO, (4% by volume) yields digests suitable for the determina- tions of Ca, K, Mg, N and P, and, if required, Fe, Mn and Na (1723).Variable high blanks for Fe, Mg and Na were traced to contamination from anti-bumping beads, which were replaced by pretreated sharp quartz sand. New Kjeldahl flasks also caused high and variable Na blanks. An alternative procedure, based upon a 2 h digestion with 1 : I H,SO, : H,O, was shown to be suitable for the estimation of Ca, K, Mg, N and P (2014). Efforts are still being made to find simple, rapid and reli.able digestion procedures that do not involve the use of HC10,.Each year this leads t o yet more published comparisons of diverse procedures for achieving sample dissolution. One such study, using four CRMs, compared wet and dry mineralization prior to the AAS determination of Cd, CU, Cr, Fe, Hg, Mn, Pb, Sb and Zn using flame atomization and Cd, Sb and Pb using graphite tube ETA (1895).Both methods were recommended for routine use in trace metal analysis.176 A ti a1 y tical A tom ic Spectroscopy Another report compared, for a range of plant samples, H,SO,/H,O, digcstion, two dry-ashing techniques, and HN03 /HClO, digestion (1035).The authors concluded that dry- ashing samples (1 g) for 4 h at 475 "C in 30 ml silica crucibles on a stainless-steel stand, followed by heating the ash with 5 ml of 2M HCl for 30 min on a hot plate gave results similar to those obtained with HN03/HC10, digestion for Cay Cu, Fey K, Mg, Mn and Zn. Wet ashing with H,SO,/H,O, gave poor results for Ca, Fe and Zn.In another investiga- tion the volatilization losses, and the tendency of some metals to be converted to forms in which they may not be readily dissolved by acid leaching, were critically discussed, with special rcfcrence to Cd, Cu, Mn, Pb and Zn (773). Where FAAS was to be used as a method of determination, it was found that a lOI-min reflux with H,SO,/HNO,/H,O, (1 ml+ 3 ml+ 3 ml per g plant material), followed by immediate centrifugation and dilution to volume with water was quite adequate (773) for digestion and leaching.A more time- consuming procedure, however, was found to be necessary prior to determination using ETA. This procedure involved ashing for 2 h at 450 "C, HCl treatment and dissolution of insoluble residues in HF, followed by further HCl treatment.Ethcrington and Davies (468) studied the loss of Fe, apparently as the pentacarbonyl compound, during convcntional wet and dry ashing procedures. All the procedures studied gave unacceptable Fe losses. They found that digestion with 2M HNO, for 6-8'h gave the best recoveries. A simple digestion procedure for Cd determinations has been described (1057).Samples (1 g) were soaked overnight with 25ml of € N O 3 , then heated at 180 "C for 4 h prior to dilution. A novel departure from the usual oxidation approach to sample preparation was reported by Piepponen and Kokka (178'8). These authors studied the use of familiar solvent extraction systems, such as APDC / MIBK, for the direct extraction from homogenized plant samples of Cd and Pb.The elements were determined using a standard addition method and ETA. The agreement of the results with those obtained after wet ashing was satisfactory. Interest in soZvent exfracfion as a separation and/or pre-concentration technique has remained at a high level, particularly in laboratories concerned with the production of reliable data on a routine basis.If high extraction ratios are used, the resulting volume of the organic phase may be small, and discrete sample nebulization distinctly advantageous. Wilson (1458) has described a system for discrete sample nebulization that is well suited to organic solvent extracts insofar as it maintains a steady flame-background absorption or emission signal. The sample portion was dropped into a small conical funnel in the usual way, but the apex of the cone passed to a T-piece in the nebulizer capillary, through which a constant stream of solvent flowed.The sample was drawn into this flowing stream. The system was satisfactorily applied to the analysis of butan-2-one extracts of Co and Cu from plant digests. Nebulization of 5O-pl portions of organic extract into a N,O/C,H, flame has been recommended for the determination of plant Mo (1170); using 31% Aliquat 336 in MIBK as extractant, centrifugation or filtration was necessary to separate the phases prior to nebulization.Procedures using extraction and conventional sample introduction tcch- niques have been described for the FAAS determination of soil Hg (3151, and for the ETA-AAS determination of plant V (1041) and soil Cd (1617).Simultaneous multi-element extractions, which exploit the inherent spectral selectivity of atomic spectroscopy, particularly AAS and AFS, to minimize preparation time, are also potentially very attractive. In a study of the determination of Cd, Co, Me, Ni and V in soil extracts by AAS using ETA, extraction of the hexamethyleneammonium hexamcthylene- dithiocarbamate complexes into butyl acetate followed by FAAS determination was used as a reference method (274).Parkcs and Murray-Smith (1055) used 0.2M dibutyl sulphide in 2,6-dimethylheptan-Lone to concentrate Au and Pd from acid digests of soils and rocks. Iu et al, (1569) extracted Cd, Coy Cu, Ni and Pb from 0.09M acetic acid, Tamm's acidA ppl ications 177 oxalate and 0.1M sodium pyrophosphate extracts of soils with dithizone in CHCl, at pH 8.5-9.5, prior to AAS determination using ETA.The solvent extraction step was necessary to eliminate interferences and multiple peaks, which occurred in some instances when the original aqueous extracts were used, especially the pyrophosphate extracts. Coextraction of Fe(II1) was masked by reduction to Fe(I1) with hydroxylammonium chloride. 4.7.2 Atomic Absorption Methods Relatively few attempts have been made to analyse solid samples of soil or plant materials directly by AAS, primarily because of the problems of sub-sampling error and scatter. Jackson et al. (956) have demonstrated, hoiwever, that the Delves cup may be used for the determination of Pb in roadside vegetation by FAAS.The samples wcrc ball-milled and mixed to a slurry with water and 50.~1 portions pipetted into the sampling cup. Other workers found that for N.B.S. orchard leaves and samples up to &mg, direct determination of the Cd, Cu, Pb and Zn contents in a 26-cm constant-temperature furnace was possible (457’). Porous graphite covers screwed into the sample crucibles reduced background absorbance by 1-2 orders of magnitude by retaining smoke particles.Non-metals are best determined in many instances by techniques other than atomic spectrometry. It has been shown, however, that the P content of fertilizer extracts may be measured directly by AAS at 21 3.6 nm in a N,O/C,H, flame (527, 1162). Indirect methods for S based on Ba determination are well known.Such a method has been applied to ammonium acetate and acetic acid extracts of soils (1248). The precipitated BaSO, was dissolved in ammoniacal EDTA solution and the Ba determined by FAAS. Hue and Williams (1717) applied a similar technique to 0.01M Ca(H,PO,), extracts of soils, adding C,H,OH to lower the BaSO, solubility and thus speed up the procedure. Graphite furnace AAS has been used as a detector for soil arsenical residues after HPLC separation (1439).Some relevant reports of interferences in AAS have been published. The acids commonly used for wet oxidation of plant samples were found to affect greatly the sensitivity of the determination of Mo by AAS using graphite furnace atomization (1877). The addition of CaCl,, disodium EDTA and NH,H,PO, was recommended to minimize the extent of such interferences, In another study it was shown that approximate matrix matching of samples and standards was essential for Mo determination using ETA (1718).A method was also suggested for overcoming furnace ageing (i.e., the effect of the number of furnace firings upon sensitivity) in Mo determinations. A series of calibration graphs was plotted using tubes of various ages, and the appropriate graph selected from time to time by injection of a suitable standard.Kubota and Ueda (775) used reduction with hydrazine sulphate to eliminate interference from Mn(VII), Cr(VI) and Fe(II1) in the cold-vapour determination of Sb in HNO,/HClO, digests of pine needles. A study of interference effects in the determination of soil Co in an air/C,H, flame showed that effects were present but below the 5% level (1214). It has been reported that for a dilute HC1 matrix, Ca suppressed the absorption of K in the air/C,H, flame (1198). 4.7.3 Atomic Fluorescence Methods The determination of Sk in HNO,/HCIOk digests of agricultural samples is of particular interest for animal dietary requirements. It has been shown that coupling hydride generation techniques to non-dispersive AFS yields an excellent detection limit of 10 ng ml-1 (510).Interference from Cu was eliminated either by double ccr-precipitation with La(OH), or by the addition of excess of Te(IV).1 78 AnalyticaI Atomic Spectroscopy 4.7.4 Atomic Emission Methods Although manufacturers continue to stress the high suitability of inductively coupled plasma OES for simultaneous multi-element determinations (see, e.g., ref. 48) in agricultural samples, only relatively recently have we seen detailed studies issuing from users’ labora- tories. In one such study N.B.S. plant CRMs were analysed both with and without Ce as an internal standard (587). The results were encouraging, the slightly low recoveries perhaps being attributable to the rather unfortunate choice of ashing conditions, although the use of Ce as an internal standard might also be open to question as the study included Ca, Cr, Cu, Fe, Mg, Mn, P and Zn.In another report that included N.B.S. orchard leaves as a CRM, stray light and line overlap interferences were found to be significant (1531). It was also found necessary to keep the salt contents of test solutions below 0.5% in order to prevent salt deposition problems at the nebulizer tip.This report covered the determination of 23 elements. In another paper, to overcome the problems associated with diverse optimum viewing heights in ICP-OES and to improve the reliability of K determinations (562) (as part of a multi-element analysis), a separate interference filter and rcd-sensitive photo- multiplier tube were used to measurc the K emission.Use is still made occasionally of molecular emission techniques in soil and plant analysis. MECA has been used for the estimation of ethylene dibrumide in fortified soils (1064). The compound was distilled into a cooled mixture of acetone/iso-octane, which was then decomposed in a Schoniger flask and the resulting solution was injected into an In-lined cavity.Butcher and Kirkbright (1 41) demonstrated the feasibility of determining NH,+ ion by treatment of samples with strong alkali and introduction of the gaseous NH, evolved into a cool-entrained air/H,/N, flame; the intensity of NH emission at 336.0 nm was mcasured, and was proportional to the NH,f-N concentration of the original solution.A comparison has been made of the A.O.A.C. official first action method for the determination of fertilizer Na by FES with AAS and ion-selective electrode methods (1430). Thc latter gave higher results, but there was also a significant difference between the results obtained by AAS and by FES.L % Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Z* 9 Table 4.7 SOILS, PLANTS AND FERTILIZERS tc For m As As Ag 328.1 Pasture plants 0-60 pg/g A As - Orchard samples 2-19 pg/g (leaves) A (leaves, fruit, soil) 0.2-40 pg/g (soil) 0.3-4.5 pg/g (fruit) A - Soils - - Seaweed - A Au B B Br 242.8 Soils 249.7 Fertilizers 249.7 Soils 376 Soils (InBr) A E E From 0.5 pg/g E (as ethylene dibromide) Ca - Plant digests - Ca 422.7 Phosphate raw materials 4&50% Ca 422.7 Plants - (as CaO) L L L G L L s G L L L Ash and dissolve 0.05 g ash in 5 mi (A) Leaves, fruit-Wash with H,O, dry, grind and digest with HN0,/H2S0, (8) Soil-Dry and digest with HCI.Continue by hydride evolution method Combined HPLC/ETA-AAS method for ,investigation of extraction of arsenical-organic residues in soils Digest with HNO,/H,SO,/HCIO, Heated cell Graphite furnace Heated SiO, cell 2M HNO, (CRA-63) Graphite furnace (23 : 1 : 23).Rebuc'e wjth Kl/&icorbic acid, dilute with HCI and add NaBH, to generate ASH, Roast at 600 "C, digest in 6M HCI, add conc. HNO,, evaporate to low bulk and take up in 2M HCI. Extract Au and Pd with di-isobutyl ketone containing 0.2M dibutyl sulphide methods compared with OES) Mix dried sample with LiF/graphite ( 1 : 3) buffer, containing GeO, internal standard (use Ge 249-8 nm).Measure SiO intensity at 250.06 nm to correct (B+SiO) intensity at 249.7 nm Form aqueous soil slurry and distil ethylene dibromide into cooled mixture of acetone/iso-octane. Decompose product in Schoniger flask and pass HBr to MECA cavity F (Chemical and spectrophotometric P A F F - - - 10 A d.c.N2/H2 Air/C,H, - Digest with H,SO,/HCIO, Graphite furnace F Air/C,H, 1699 $ 1135 1439 1979 1055 1429 1740 1064 495 1237 1723 v;Table 4.7 SOILS, PLANTS AND FERTILIZERS - contirzued Element X/nm Matrix Concentration Tech* Sample treatment Atomization Ref. Form Cd 228.8 Contaminated soil and 0-2 pg/g (plants) A pasture 2-12 yg/g (soils) Cd Cd Cd Cd Cd c o c o c o - Plants 0.05-1 @g/ml A (in extract) 228.8 Soil extracts, sediments From 0.5 ng/ml A (direct) From 0.1 ng/ml (in extract) A - Plants - 228.8 Soils Trace levels A - Plants (Geissois species) Up to 2.3% (NI) A pg/g levels (Co, Cr) 240.7 Sand and clay soils 5 pg/ml level A 304.4 (in extract) 346.6 347.4 240.7 Plants 0-1 pg/g A Cr - Plants (Geissois specles) Up to 2.3% (Ni) and A LLg/g levels (Co.Cr) L L L L L ~ ~~ ~~ (A) Soils-Sieve (6&mesh), dissolve i n F - 1036 HF/HNO,, evaporate and redissolve in 2M HCI (B) Plants-Wash, dry at 105 "C, ash at 450 "C and dissolve i n 2M HCI Soak 1 g sample overnight i n 25 ml F - 1057 HNO,. Heat to 180 "C until clear and dilute as required with HNO, (1 : 1) Mix (1 : 1) with graphite, ash at Flameless 1415 450-500 "C and atomize at 1800-2000 "C on non-flame electrically-heated evaporator Extract solution with APDC/MIBK and Graphite furnace 1617 back-extract with HNO,.Use Zr-coated F - graphite tubes evaporator Homogenize and extract with dithizone Graphite furnace 1788 into MIBK, for Cd, Pb Extract with APDC/MIBK and back- Graphite furnace 2034 extract with HNO, (See Cd, ref. 1617) (HGA-76) Ash leaves at 500 "C and dissolve ash F - 1059 in 2M HCI. (Study of hyper-accumulation Graphite furnace of nickel) Study of experimental parameters and F Air/C,H, 1214 of interference by Fe, At, K, Na, Mg, Ca Separate Co, Cu by chelation/solvent F - 1458 extraction, evaporate extract t o dryness and dissolve i n ethyl methyl ketone. Take 300 aliquots, using modified pulse-nebulization apparatus See Co.ref. 1059 F - 1059 Graphite furnacec u - Plants, sediments Trace levels cu c u cu CU Fe Fe Hg - Soils 2-50 pg/g 324.7 Contaminated soil and 2-15 pg/g (plants) - Plants 0 . 2 4 pg/ml pasture 40-1 60 pg/g (soils) ( i n extract) 324.7 Plants 0-2 p g / g - Plants u p to 0.1 Yo 248.3 Plants - - Soils Trace level8 - Aquatic plants - Soils 253-7 Seaweed Up t o 460 ng/g 1-100 ng/g - Soils, vegetation, From 10 ng/g environmental samples 253.7 Soils - A A A A A A A A A A A A A L L L L L L L L L, G G L, G G G Dry, digest with HNO,/HCIO, i n PTFE vessel, stand, dilute with H,O and filter.Add malonic acid, adjust to pH 5 with NH,OH and pass through Dowex A-1 resin column. Elute Cu, Pb and Zn with 2N HNO, Digest with HCI/HNO,, followed by HF, evaporate to dryness at 120 "C.Add HNO,, evaporate, add HCI, evaporate, dissolve in 1M HNO, and dilute to volume (2-5 ml for 0.5 g sample) See Cd. ref. 1036 F F F See Cd. ref. 1057 F See Co, ref. 1458 F Digest over period of 6-8 h i n 2M HNO, F See Ca, ref. 1723 F Prepare acid extract and add KCNS to F final concentration of 0.02M. Extract with 5-(4-pyridyl)-nonane into C,H, and back- extract Hg with HNO,, Na citrate or Na thiosulphate solution Air/C,H, - - - - - Air/C,H, Air/C,H, - Cold vapour - Cold vapour Digest with HN0,+V20,, heat t o 160 "C, Cold vapour (overnight), warm to 100 "C (24 h) then to 155 "C (1: h).Add KMnO, to slight excess and dilute t o volume for cold vapour method Digest with HNO,+V,O,, heat t o 160 "C, add conc.H,SO,, heat and dilute (0.5 g sample to 100 ml). Reduce with SnCI, (A) Digest with HNO,/H,SO, and add KMnO,, at water-bath temperature (B) As for (A), but at elevated temperature Cold vapour Cold vapour U 2 1032 1036 1057 1458 468 1723 31 5 665 1039 1456 1644 1928 c. 00 c.c- Table 4.7 SOTLS, PLANTS AND FERTILIZERS- continued oo t 3 Element X/nm Matrix Concentration Tech* Sample treatment Atomization Ref.Form Hg - Soils K - Plant digests K - Plant materials K 404.4 Plants K - Ferti I izers K 766.4 Plants K - Soils Mg - Plant digests Mg 285.2 Phosphate raw materials Mg 285.2 Plants Mn - Soils Mn 279-5 Plants Mo - Plants Mo 313.3 Plants Mo - Plants N 336.0 Soil extracts (NH,+) (NH band) Na - Fertilizers Trace levels 10-55 pg/ml ( i n extract, as K,O) - Up to 5% (as MgO) - 6-3400 jLs/s 0.2-20 pg/g - 0-40 ng/rnl ( i n extract) - 0-500 pg/ml (in extract) - A E E A E E E A A A A A A A A E G L L L L L L L L L L L L L L G A, E L Comparison of NaBH, and SnCI, as reducing agents, coupled with Au amalgamation to collect Hg vapour - F Air/C,H2 - P ICP Dry-ash and dissolve in HCI.F Air/C,H, (Study of interferences by Ca and HCI) interference and L i as internal standard See Ca, ref. 1723 F Air/C,H, Use of calculator for cubic regression F - calibration curve - F Air/qH2 - Graphite furnace See Ca, ref. 1723 F Air/C,H, Cold vapour Add La to overcome phosphate F - See Cu, ref. 1032 F - See Ca, ref. 1723 F Air/C,H2 Ash at 540 "C and dissolve i n HCI. Add H3P0, + H,O, and extract with 3% solution of Aliquat 336 in MIBK. Determine Mo in organic phase by pulse-nebulization method (50 sample) Digest with HNOJHCIO, Graphite furnace Detailed study of matrix effects, Graphite furnace covering acids, salts, anions, cations and pH effects Add H,SO, (12.5% V / V ) to sample F NJH, solution, followed by NaOH (48% m / V ) .Sweep evolved gas to flame and integrate signal at 336.0 nm Comparison of methods, including FES F - and FAAS F N,O/%H, (HGA-2100) 1936 495 562 1187 1431 1723 1903 495 1237 1723 1032 1723 1170 k % % v 1718 2. 1877 k 2. 2 141 T 1430Na - Ni - P 213.6 Pb - Pb - Pb 217-0 Pb - Pb 217-0 Pb - Pb Pd Pt S (SO,) Soi Is Plants (Geissois species) Fert i Iizers Plants, sediments Roadside vegetation Contaminated soil and pasture Plants Roadside pasture Soils Plants Soi Is Plants; nutrient solutions Soi Is Soils Soils, plants Up t o 2.3% (Ni) and pg/g levels (Co, Cr) l M 6 % (as P,O,) Trace levels Trace levels 0-30 (plants) 50-230 lug/g (soils) 0.5-10 pg/ml ( i n extract) 1-20 pg/g (as sulphate) 0 . 1 6 5 - 0 pg/g E A A A A A A A A A A E A A A L L L L L L L L L L L L L L G See K, ref. 1903 F - See Co, ref. 1059 F - Extract with H,O or dilute acid F N,O/CJ+z See Cu, ref. 764 F Air&H, Dry, grind, slurry in de-ionised water F Air/C,H, and transfer 50 aliquot to Delves ( + Delves cup) micro-samp ling cup See Cd, ref. 1036 F - See Cd, ref. 1057 F - Wash, dry-ash slowly to 450 "C and F - dissolve residue i n 2M HCI (A) Treat and evaporate ( x 3) with F Air/C,H, HF/HCIO, and dissolve residue in 3N HCI (6) Oxidize organic matter with HNO,. add HCIO,, evaporate, extract with H,O and dilute with U.1N HNO, See Cd, ref. 1788 See Au, ref. 1055 Graphite furnace F - Study of Pt absorption P - (A) To determine soluble SO,, extract F - with NH, acetate/acetic acid, precipitale extracted SO, as BaSO,, filter, dissolve in NH,OH/EDTA and determine 6a HNOJHCIO, and proceed as in (A) (B) To determine total S, digest with Extract with 0.01M Ca(H,PO,),,.F N,0/C2H2 Precipitate BaSO, from alcoholic solution Digest with HN0,/H2S0,/HCI0, and follow hydr ide-evolut ion procedure Heated SiO, tube 1903 2 1059 E 527 $ 1162 764 956 1 036 1057 1134 1243 1788 1055 469 1248 1717 168 l-- ccTablc 4.7 SOILS, PLANTS AND F~RTTI,TZERS-cconfinued c E lern ent X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form Sb 217.6 NBS pine needles; waters Trace levels A A F A A A A A E A E - A L L G L L L L L L L L - L Prepare sample i n 3M HCI medium and F - 775 reduce with NaBH,.A preliminary reduction with hydrazine sulphate prevents interference by Mn(VII), Cr(VI) and Fe(l1l) Wet-ash with H,SO,/HNO,, treat extract Heated SiO, tube 2058 with KI and reduce with NaBH, Digest with HNOJHCIO, at 200 “C and F Ar/H, 51 0 add KBr t o convert Se to Se( IV) .Add 5% La(NO,), solution, followed by NH,OH and dissolve precipitate in 5M HCI Sb se 217.6 Vegetation, soils - Soils From 0.3 ng/ml ( i n extracts) Trace levels V 318.4 Plants 0.5 fig f g leve Is Wet-ash with HNOJHCIO,, add KMnO,, solution to oxidise V(1V) t o V(V), and extract with N-cinnamoyl-N-(2,3-~ylyl) hydroxylamine (CXA) into CCI, See Cu, ref. 764 See Cu, ref. 1032 See Cd, ref. 1036 Graphite furnace 1041 Zn Zn Zn - Plants, sediments - Soils 213.9 Contaminated soil and pasture - Plants Trace levels 3-140 0-30 pg/g (plants) 1 5 ~ 2 0 pg/g (soils) 0.05-1 pg/ml ( i n extract) All levels Air/C,H, 764 I 1032 - 1036 Zn See Cd, ref. 1057 - 1057 Various (61 1 Various (8) (200) Various - Soils, plants I CP - 48 50 - Soils, plants All levels b .% 51 3 D.c.arc plasma ;i’ I Plants All levels Various - Plants All levels Description of standard reference materials (SRM) for plant tissue analysis Extract with 1M NH, acetate for Cd, Co, Graphite furnace 274 2 Ni or Tamm’s oxalate reagent for Mo, V (CRA-63, cl HGA-76.B) 0 2 Various (5) - Soil extracts Trace levelsVarious - Plant tissue; soil extracts - ( 8 ) Various - Plant tissues ( 8 ) Various - Soils and sediments (1 0) Various - Vegetable matter (5) Trace levels Trace levels Various - Orchard leaves Trace levels A S A, E L E L A L A L Various - Plants Trace levels Various - Horticultural samples Trace levels (7) A L A L Direct method.Up to 8 mg sample without ashing or 30-50 mg sample with some ashing. Results quoted for Cu, Cd, Pb, Zn Extract soils with 1M NH, acetate. F Air/C,H, Digest plant material with HNO,, under pressure, dilute and add 5000 pg/ml La to all solutions Ash overnight at 500 "C, dissolve in HCI P ICP and dilute lo volume, equivalent to 1 g sample in 25 rnl 10% HCI.Add Ce as internal standard to overcome suppression by K Method covers Co, Cu, Pb, Mn, Ni, Zn F - and, with addition of La solution, Ba, Ca, Sr, V Study of errors arising from ashing of F Air/C,H, vegetable matter samples.Two procedures are recommended : (A) Dry at 75 "C, grind, digest with Graphite furnace Graphite furnace H,SO,/HNO,/H,O, (1 : 3 : 3), centrifuge and dilute with H,O (B) Dry, grind, heat slowly to 450 "C, treat with HCI, filter, treat any insoluble matter with HF, evaporate and dissolve in HCI Method (A) i s recommended for flame methods only Ash at 550 "C and dissolve in HCI.F Air/C,H, (Study of trace elements in plants grown on exlreme soil types) Comparison OF 4 sample treatments : F - (A) Wet-ash with HNOJHCIO, (6) Wet-ash with H,S0,/H,02 (C) Dry-ash (no detail available) (D) Dry-ash at 475 " C in covered SiO, crucible and dissolve ash in 2N HCI (preferred method) Elemenls : Fe, Mn, Zn, Cu, Ca, Mg, K 457 I L % -. %. 471 2 587 706 773 994 1035 r-. Go wlTable 4.7 SOILS, PLANTS AND FERTILIZERS-continued ~ ~~ ~~ ~~ ~~~ ~ ~~ ~ ~ Element X/nm Matrix Concentration Tech* Samp!e treatment Atomization Ref. Form Various (10) Various Various Various (23) (5) Various (12) Various (111 Various (9) Various Various Various Various (51 Cabbage plants and roots Vegetable matter Orchard leaves, soils (NBS/SRM) Soil extracts Soik Soi Is Plants Soi Is Pepperbush powder Soils, plants, fertilizers Plants Major levels pg/g levels (from 0-2 CU, to 100 Sb) All levels Trace levels Trace levels - Major levels (Na, K, P, Ca.Mg) A - E A E A A A E, A A. E A, E L - L L S L L, G L L L L Rinse with H,O, dry, grind and digest F - with HNO,/HCIO,/H,SO, (5 : 2 : 1). Hg i s determined by cold vapour method and V, Cr, Mn, Fe, Co, Ni, Cu, Zn and Cd by FAAS. (Study of heavy metal toxicity) Discussion of new results on standard - - reference materials Study of operating conditions. Prepare P ICP solutions at < 0.5% total salt content Reduce F e ( l l l ) to Fe(ll) with NH,OH.HCI and extract ( x 2) at pH 8.5-9.5 with dithizone/CHCI, (Cd, Cu, Co, Ni, Pb) Ignite at 450 "C and mix (1 : 1) with buffer of Li,CO,/graphite (1 : 9) containing 0 05% ln20, (internal st and ard ) Cold vapour (Hg) Graphite furnace (HGA-74) A 10 A d-c. - F - Graphite furnace Graphite furnace Cold vapour Comparison of wet- and dry-ashing F Air/C,H, sample preparations, for determination of : Cd, Cu, Cr, Fe, Hg, Mn, Pb, Sb, Zn (FAAS); Cd, Sb, Pb (ETA-AAS) and Hg (cold vapour) Review (57 refs.) F - Analysis of new standard reference F Air/C,H, sample. Wash, dry, grind and homogenize Graphite furnace leaves and wet-ash with HNO,/H,O,. Determine Zn, Fe, Mg, Mn by FAAS; Co, Cd, Pb, Cu by ETA-AAS and Ca, K by FES Review - - We t-as h with Na2S0,/H,S04/H 202. F Air/C,H, Dilute with H,O and add La solution (I50 mg dry sample to 25 ml) N O/C, H, 1058 1521 1541 1569 1618 1764 1895 b !% 1905 z. 1934 s 4 $ G* k 2014 2 1984 3 s 0

ISSN:0306-1353    

DOI:10.1039/AA9790900175

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

Applications 187 4.8 FOODS AND BEVERAGES The dependence of the toxic or nutritious effects of a given element on its form of combina- tion were stressed in ARAAS 1978, 8, 154. It was suggested that when legislation i s prepared it should define not merely the maximum permissible quantity of an element, but rather the acceptable levels for each of the different forms in which it is known to occur.Certainly the literature reflects an increasing interest in speciation. Diamondstone and Hanamura (181) studied the forms of As in oysters by utilizing differences in volatilization temperature between the various forms. Castello and Kanitz (4109 studied methyl- and ethyl-mercury levels in tuna fish and human tissues using GC! with an electron capture detcctor, and checked thc total Hg recoveries using a conventional AAS method.Lee and Clydcsdale (1034) determined total, elemental and soluble Fe forms in foods by AAS. Japanese workers (1809) have reported the determination of organic Hg compounds in rice using TLC followed by AAS. Even when coupled with species separation, elemental analysis of foods and beverages may fail to give an indication of dietary input. It may be dcsirablc therefore to extract the food or beverage in a way representative of the ingestion mcchanism.Hence Tsushida (1789) boiled tea samples for 5min with water, filtered them, and determined Cd, Cu and Pb in the aqueous extract, Clearly a more vigorous prc-treatmsnt would not simulate the likely intake to the body. Certified reference materials play an important role in establishing the accuracy of proposed methods, but thcy continue to be available for only a limited number of materials and from few sources.The National Bureau of Standards, however, is steadily increasing the variety of CRMs available; those of interest to analysts studying trace elements in foods and beverages have been described by Alvarez and Rains (1434).Tried and tested methods that can be used as reference methods often save the analyst considerable development time. The reference method for Cu in foodstuffs evaluated by WPAC has now been published (627). A number of reviews have appeared summarizing the analysis of foods and beverages. Welz et d. (533) and Fricke and co-workers (1991) reviewed the use of AA techniques in food analysis, and Paus and Enger (9.639 reported on methods of sample preparation. 4.8.1 Sample Preparation Many new sample preparation procedures for materials that can already be analysed quite satisfactorily using known methods are still appearing in the literature. It would appear that the only basis for publication in many of these i s that the method proposed is different from those previously reported; little account is taken of whether or not it provides significant advantages over existing methods.Moreover, some of the procedures are so complicated that the high accuracy and precision claimed are unlikely to be maintained in continued routine application, Some reports have appeared of methods involving minimal sample preparation (375, 709, 1619). If care is taken to confirm their accuracy and precision, the Lise of these simplified procedures should lead to long-term efficiency and reproducibility.Piepponen and Kokko (972) claimed efficient extractions of Cd and Pb from honz- genized foods without oxidative digestion. The food was buffered at pH 10.2 and extracted with dithizone/MTBK; the organic extract was analysed directly by AAS using ETA.The recovery and precision were improved when sodium 4( 1,3,5,7-tetramethyloctyl)benzene sulphonate was used to lower the surface tension in the homogenization step. The accuracy of the results was checked using N.B.S. CRMs and good agreement with the certified values was obtained. Jones and Boyer (1065) overcame the inhomogeneity of canned-food samples by mixing them with an equal mass of HNO, and thoroughly blending them in a high efficiency probe-type Polytron homogenizer; other workers used a high-efficiency sonic-probe homogenizer to similar effect (1440).188 Analytical Atomic Spectroscopy For the determination of Cr in animal feeds, Hyran and Collins (46) compared an existing method, which used HCIO,, with a block digestion technique carried out at 450 “C using a Mjeldahl protein catalyst. They found the results from both methods agreed well, but preferred the new method as it eliminated the need for using HCIO,.Contamination from any source is to be avoided and Caper and Boyer (620) have again reminded us of the problems encountered in the analysis of canned foods. Fctteroff and Syty (1037) found contamination arising from glassware when determining Pb in chewing-gum. 4.8.2 Atomic Absorption Methods A general study of the application of AAS to food analysis has been presented by Grobenski et al, (995).The additional difficulties associated with ETA compared with flame atomization continue to be a problem in laboratories performing routine analysis. In the past limited sample volumes have sometimes excluded the possibility of flame atomization.However, in rccent years discrete sampling methods have significantly extended thc utility of flame mcthods and Wolf and Stewart (1438, 1708) have published a method where microsamples (25-300 pl) were introduced into a solvent stream leading to the nebulizer. They described the technique as “Automated Multiple How Injection Analysis” (AMFJA) and it appears to have considerable potential for use in laboratories with high sample throughputs.Mercury continues to attract considerable attention. Sluddendorf et al. (14’33) described a simplified apparatus for the determination of Hg in fish by the cold-vapour technique. Oelschlaeger et al. (417) made a detailed study of contamination problcms and interferences in the determination of Hg in foods and for the same determination a group of Chinese workers studied interference effects, particularly from H(NO)SO, (141 1).Little fundamentally new material has appeared on FAAS. Similarly for dectrotherrnaZ atomization most of the reported work has concentrated on variations on established themes. Azuma and Aramaki (1212) reported a detailed investigation of P using ETA and an EDL source.A comparison of interference effects in the determination of Pb using both constant-temperature and conventional electrothermal atomizers (1 547’) has been made. Once again Ni addition has been found to be useful in the determination of Se using ETA (335). In recent years there has been a revival of interest in atomization from metal surfaces; Ohta and Suzuki (1469) used a Mo microtube to determine Sn in canned foods. They found H, in the purge gas increased the efficiency of atomization and that the addition of €I,PO, lowered the atomization temperature and depressed interferences. The detection limit was 8.6X 10-12 g.The introduction of 0, to the otherwise inert gas stream of an ETA was found to significantly reduce non-specific absorption, and the authors claimed no negative influence on the lifetime of the graphite tubes (995).Considerable caution, however, is required if this approach is to be used on a routine basis. Various background correction methods are now used in food analysis by AAS. Kumpulainen et 01. (445) determined Cr in foodstuffs using ETA and a continuum-source echelle monochromator wavelength-modulated AA spectrometer.Kaykaty and MacDonald (1437) found they could determine Se in multi-component fced matrices with little OT no sample pretreatment using ETA and a Hitachi Polarized Zeernan Effect AA spectrometer. Like other workers (see Ref. 335) they found the use of Ni advantageous in the ETA stage. 4.8.3 Atomic Emission Methods The use of MIPS has been rather limited in this area, although Milligan et al.(1 385) described the use of an MIP as an element-selective detector for GC for determining polybrominatedA ppl icat ions 189 biphenyls in food samples. Use of ICFs on the other hand is becoming more widespread. Capar and Gould (44), for example, used an ICP to determine Al, Cr, Cu, Fe, Mn, Mo, Ni, Ti and Zn in foods.Procedures based on d.c. arc OES have been described for the determination of Pb in cercals (504), Pb and Sn in canned meat (1161) and trace heavy metals in the brine of canned vegetables (1 620, 1700). 4.8.4 Comparison of Methods McHaro ef al. (1713) compared FAAS, FAES, FAFS, d.c. plasma AES and ICP-AES for the analysis of orange juice. They studied Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Rb and Zn.Precision and limits of detection were given for all possible element /instrument combina- tions. FAAS gave the best overall precision, but the conclusions were complicated by variations in preparation procedures. Also, much of the work was done on “in-house” built equipment, which gave problems not generally associated with modern commercial equipment.Table 4.8 FOODS AND BEVERAGES 0 E leme n l X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form As - Foods AS 193.7 Foods AS As As AS - Oysters 193.7 Pig feeds and faeces - Foods - Offal, fish As 193.7 Coffee Ca - Beer Ca - Fodders Ca - Poultry meat Ca 422.7 Pig feeds and faeces A A From 0.1 A From 5 ng A (absolute) ng/g levels A A E 2.0-2-5 mg/g level A ( i n extract) 40-1 600 pg/ml A G G L L G G L L t L L Detailed study of acid digestion + Heated SiO, tube hydride evolution method for As and Se Ash, dilute, digest with H,0/H202, treat with HNO, and dilute t o final volume i n 5% ( V / Y ) H,SO,.Proceed by hydride- evolution method, to determine As, Sb, Sn. If necessary, remove Sn by cupferron/CHCI, extraction before As.Sb analysis Thermal separation technique applied to P As speciation study Digest 2 g sample with HNO,, followed by HCIO,/H,SO,/molybdate mixture. Dilute t o 50 ml and calibrate by standard addition method. See also “Various”, ref. 512 Hydride-evolution method, using NaBH, F F (9 : 2 : l ) , cool, add HCI and dilute with H,O. Reduce with NaBH, after addition of (a) 50% HCI, for Se determination or (b) 0.0125M EDTA for As determination Digest with H,SO,/H,O,, after initial treatment with HNO, in pressure vessel (see Hg, ref. 1249) ( In t er-l a bora t ory trial ) buffer material containing KH,PO,, HCI, AICI,, MgSO, + surfactant F F Digest with H NO,/H,SO,/H CIO, F Add LaCI, to final solution. Wet-ash with H,SO,/H,O, and add F F F F - Digest 2 g sample with HNO,, followed by HNOJHCIO, and dilute to 100 ml.See also, As and “Various”, ref. 512 Air/C2H2 I CP NJH, N21H2 Air/propane - - - - Air/C2 H, 47 145 181 512 757 758 1249 a, v 2. 301 ’ & 377 3. 390 s c, 512 2 2Ca 422.7 Milk Cd 228.8 Rice Cd Cd Cd Cd Cd Cd Cd Cr Cr - Milk 228.8 Foods 228.8 Sea-foods 228.8 Coffee - Foods - Tea - Wines - Feeds 357.9 Diets Trace levels (from 0.005 pg/g) ccg/g levels ng/g levels Trace levels (From 1 ng absolute) Not detected - 0 * 2-1 * 0% 0-40 ng/ml (in extract) A A A A A A A A A A A L L L L L L L L L L L Add LaCI, to de-proteinized sample.F Air/C,H, (comparison of FAAS method with 2 FES methods and 1 titration method) Ash in low-temperature plasma asher F Air/C,H, for 10 h, char residue with conc. H,SO, and treat with H,O, until clear.Neutralize with NH,OH, add Na tartrate solution and extract with NaDDC into MlBK (A) Freeze-dry i n Teflon tubes and digest, under pressure, with HNO, at 150 "C. Dilute to volume {B) As in (A), omitting digestion step Homogenize sample in buffer solution (pH 10.2) with addition of surface- tension-lowering agent, 4-( 1,3,5,7- tetramethyloctyl) benzene sulphonate.Extract Cd, Pb directly with dithizone/ MlBK Freeze-dry, weigh and ash in 0,-flow. Dissolve residue i n H,O+few drops HCI/HNO,, dilute and use 20 Prepare solution as for determination of F - As (ref. 1249), add NH,OH and extract Cd, Pb with DDC/xylol Digest with HNOJHCIO, and extract Cd, Pb with APDC/MIBK at pH 1.4-1.8. Back-extract with HNO,/H,O, and buffer with NH,O H /NH,H,PO, Extract with boiling water (3 g /lo0 ml) Graphite furnace filter and analyse 5 portions - Graphite furnace Digest with Kjeldahl protein catalyst + F - H,S0,/H,02 at 425 "C i n block digestion assembly Homogenize, ash dried sample (150-200 Graphite furnace rng) at 500 "C, treat with H,O,, evaporate, (HGA-2100) re-heat to 500 "C and dissolve in I N HCI.(Alternative treatments also discussed) Graphite furnace Graphite furnace Graphite furnace aliquots Graphite furnace (HGA-2000) b 1637 'g r;, 3 173 2. 501 2 391 972 1222 1249 1543 1789 1904 46 445 r-. \oc. \o Table 4.8 FOODS AND BEVERAGES- coiztiiiued Element h/nm Matrix Concentration Tech. Form Sample treatment Atomization Ref. c u - Feeds - (copper-supplemented) A cu - Beer cu 324.7 Foods - A From 0.05 @ / g A cu 324.7 Food digests 0-50 p g / g A c u - Tea 83-127 pg/ml A (1st extract) 27-64 p g / m l (2nd extract) cu - Wines - A Fe - Canned foods - A Fe Fe FO FS - Beer - Edible oils 247.8 Pork 248.3 Foods - A Trace levels A 5 ccg/g levels A 0-10 p g / r n l A (in extract) Fe - Sake, beer, wine, vinegar - A Hg - Mineral feeds 0.01-0.23 pg/g A L L L L L L L L L L L L G Prepare aqueous slurry, add Mg(NO3),.6H,O, dry and ash.Extract with acid for AAS analysis See Ca, ref. 301 Digest with HNO,/H,SO, evaporate t o remove HNO, and complete digestion by addition of H,O,. Adjust solution to pH 3 and extract Cu with APDC/MIBK Inject sample volumes) into stream of solvent flowing continuously t o nebulizer. (AMFIA technique) See Cd, ref. 1789 (A) Digest with HNO, in sealed polystyrene vessel at 70 "C for 4 hr (Fe, Pb) (6) Digest with HCI/H,O, in same containers at 70 "C for 30 min (Fe, Sn) See Ca, ref. 301 Extract with aqueous acid, from an oi I/CH C l 3 em u ls ion Dry-ash, extract with HCI and dilute to 0.2N HCI in final solution Methods for determination of total elemental and soluble Fe by FAAS and Fe( i l ) , Fe( 111) and Fe complexes by colorimetric met hod None Use NaBH, reduction F Air/C,H, F - F Air/C,H, F Air/C,H, Graphite furnace Graphite furnace Graphite furnace (CRA-63) F - F - F - F Air/C,H, Graphite furnace Cold vapour 296 301 627 1708 1789 1904 43 k 301 Q 375 e 378 b 1034 z.B s $ h 1414 2 417 9 0- Foods 253.7 Coffee A ng/g levels A - G G G G L, G L L L L L L L L L L L L Cold vapour Cold vapour Cold vapour Cold vapour Cold vapour b 2 410 1249 2 -. 2 1264 141 1 1433 1809 1892 51 2 1033 6 38 377 512 1075 43 44 375 391 Digest with 65% HNO, at 190 "C in sealed vessel. Reduce with NaBH, i n presence of NH,OH (See also, As, Cd, Pb, ref. 1249) Extract with butyl acetate and reduce with SnCI, i n the presence of Cu(l1) Digest with V,O,/HNO,/H,SO, Trace levels A - Fish meat - Foods - Fish - Rice Trace levels A 0.01-1 pg/g A From 5 ng/g A - - Air/C,H, - Air/C,H, - Air/C,H, Air/C,H, Soak in HCI overnight, clean by thin-layer chromatography, digest with HNO,/H,SO,/KMnO, and extract with d ithizone/CH CI, - - F F F - Wines 404.4 Pig feeds and faeces 2-8 ng/ml A 20-800 pg/ml A 6 1 300 pS/g A (,in extract) (various foods) See Ca, ref. 512 - Foods Homogenize in H,O, dry at 9C95 "C, ash at 450 "C and dissolve in 3N HCI.Dilute, with addition of SrCI,, to give 0.1% Sr in final solution. For liquid samples, dilute with SrCI, solution. (Results given for 150 foods) Shake to remove excess CO,. With suitable aliquot (up to 4 ,Lg Mn), buffer Mn 279.5 Carbonated drinks 8-13 ng/ml A to pH 8 with NH,OH + NH,CI and extract Mn with 4-benzoyl-3-methyl-l-phenyl-5- pyrazolone (BMPP) into MlBK See Ca, ref. 377 F See Ca. ref. 512 F Na Na - Fodders 330.2 Pig feed and faeces 232.0 Marine foods E A - 4-1 600 pg/ml ( i n extract) UP t o 9 pg/g A Ni Freeze-dry, ash (LTA), dissolve in HCI, evaporate and redissolve in 0.5M HCI F Pb - Canned foods - A See Fe, ref. 43 Graphite furnace (CRA-63) F - F - Graphite furnace Pb Pb Pb - Bone meat - Edible oils - Milk - A Trace levels A 5 ng/g A - See Fe, ref. 375 See Cd, ref. 391Table 4.8 FOODS AND BEVERAGES- conrimed Element h/nm Matrix Concentration Tech. Form Sample treatment Atomization Ref. Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Sb - Cereals - Foods 217.0 Chewing-gum - Canned foods 283.3 Foods - Preserved duck eggs - Canned foods - Foods 217.0 Livestock feeds - Tea - Canned meat 283.3 Sea-foods 283-3 Coffee - Wines 217.6 Foods 40-120 ng/g (cereals) (total diet) Trace levers (from 0.05 pg/g) 8-15 ng/g 0.06-0-63 pg/g Trace levels Trace levels Trace levels (from 20 ng absolute) Trace levels 0.613.3 pg/ml - pg/g levels ng/g levels - - E A A A A A A A A A E A A A A S t L 2.L L L L L L S L L L G Dry-ash at 500 "C for 24 h and store in polyethylene containers A - See Cd, ref. 972 Graphite furnace Ash gently at 400-450 "C, treat residue Graphite furnace with HNO,, evaporate and ash at 500 "C.(HGA-2000) Redissolve in HNO, and dilute Homogenize bulk sample (150-500 g) F - by addition of dilute HNO, (1 : 1) and blend in Polytron homogenizer. Dry- or wet-ash sub-samples for analysis Digest with HNO,/H,SO, dilute with F - H,O/H,SO, and extract with DDC/xylene Digest with HNO, in PTFE pressure vessel F - Add 2N HNO, and blend in ultrasonic F - homogenizer.Digest sub-sample with HNOJHCIO, (4 : 1) or HN0,/H,S0,/H20,. Extract Pb with APDC/butyl acetate See Cd, ref. 1543 Digest with HNO, and atomize at 1900 "C. Calibrate by standard addition method See Cd, ref. 1789 Chlar20g de-fatted sample at 100 "C and A 12 A ash at 450 "C. Transfer ash directly te C electrode See Cd, ref. 1222 Graphite furnace Graphite furnace (Woodriff) Graphite furnace (HGA-2100) Graphite furnace See Cd, ref. 1249 F - - See As, ref. 145 Graphite furnace F Air/C,H, 504 972 1037 1616 1 065 1413 1432 1440 1543 1547 1789 1161 1222 1249 1904 145Sb Se Se Se Se Si Sn Sn Sn Stl Sn ( Vendex) Sn Sn Sn V Zn Zn 206.8 Dry yeast - - Foods 196.0 Feeds - Feeds - Offal, fish I Milk d From 0.1 pg/g From 5 ng (absolute) From 2.8 ng (absolute) - Canned foods - - Foods - 224.6 Foods - Foods - Foods (Fruit, tea) From 0.2 pg/g From 5 ng (as HMPD) - Canned meat - 224.6 Canned foods - - Fruit juices 0-05 &g/ml level 318.4 Edible marine species Up to 7 - 4 pg/g - Edible oils Trace levels (in extract) 213.9 Pork 0-2 @rnl A A A A A A A A A A A E A A A A A L G L L G L L L G G L S L G L L L Digest with HNO,/H,SO,.Add HCI, H,PO,, followed by Rhodamine B and extract with C,H,. Determine Sb by ETA-AAS (or colorimetrically at 565 nm) See As, ref. 47 Digest with HN0,/H,02 in autoclave, add HCIO, to digest and evaporate, with addition of Ni to retain Se (A) For Se (as selenite) in poultry and hog feeds, extract with H,O (B) For total Se, wet-ash with HNO, In all procedures, add NINO, solution t o avoid loss of Se at ashing stage See As, ref. 758 F Air/propane Dilute (1 : 1) and apply directly to ETA. Calibrate by standard additions method, using N%SiO, solutions See Fe, ref. 43 Digest with HNO,/H,SO, and add CH,OH F N,O/qH, to final solution See As, ref. 145 F Air/C,H, See As, ref. 757 F NJH, Method for determination of Vendex or distannoxane (HMPD) .Extract sample homogenate with ethyl ether + 1 YO acetic acid, separate on SO,-gel column and determine Sn by ETA-AAS Treat with H,PO, to reduce interferences Mo microtube and add H, to argon purge gas flow Reduce acidified solution with NaBH, F NJH, See Ni, ref. 1075 Ash and dissolve in 0.2N HCI F Air/C,H, Graphite furnace Heated SiO, tube Graphite furnace Graphite furnace Graphite furnace Graphite furnace (CRA-63) Graphite furnace hexakis (2-met hyl-2-p heny lpropyl) (HGA-2100) See Pb, ref. 1161 A - furnace ( + long-path cell) Graphite furnace See Fe, ref. 375 F - $ -. 47 2 335 1437 758 709 43 45 145 757 1069 1161 1469 1779 1075 375 392 cc. Table 4.8 FOODS AND BEVERACES-ccoi7ti~iued \o o\ Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form Zn Tannins (indirect) Poly- brom i nated biphenyls (indirect) Various Various (9) (6) Various (6) Various Various (25) Varlous (6) Various (81 Various ( 8 ) Various 213.9 Food digests 324.7 Tea (CU) - Foods - Bone meal - - Edible oils @g/g levels - Pig feeds and faeces pg/ml levels (in extract) A L See Cu, ref. 1708 F Air/C,H, 1708 A L Precipitate tannins from aqueous tea F - 1159 extract by addition of Cu acetate.Filter and digest with HNO,/H,SO, E 0 Extract and separate by GLC P MIP 1385 A - Foods - E - Canned foods - - Edible oils and fats Trace levels A - Balsamic vlnegars pg/ml levels (from 6.00 A - Foods Major (Ca, Mg, K) A for Mg t o 1.5 for Pb) and trace (Cu, Zn, Fe, Ni, Mn) levels - Foods Trace levels A L L L L, s L L L L L Elements quoted : Al, Cr, Cu, Fe, Mn, P ICP Mo, Ni, Ti and Zn addition of Mg(NO,), solution at charred stage (Pb, Cu, Cd, Mn, Zn, Fe) Digest with HNO,, followed by HCIO, F Alr/C,H, and dilute to volume (2 g/100 ml).Calibrate. using 25 ml aliquots, by standard addition method (Cu, Zn, Fe, Mg). Extract similar aliquot with APDC/MIBK (pH 4.0) (Cd, Pb) Review of AAS techniques applied to F - food analyses Graphite furnace Digest with HNOJHCIO,.(Quantitative P ICP results for Al, Ca, Cu, Fe, Mg, Ni, P, Sn, Ti and Zn) Digest with HCI (1 : 1). Method for Cu, Fe, Ni, Zn, Pb, Cd Results given for Mg, Ca, Fe, Mn, Co, F - Zn, Cu, Pb Ash in restricted air supply, with F - Graphite furnace Review of sample treatments F - Review F - Graphite furnace 44 331 51 2 533 b 620 3 3 3 677 % b S' 704 $ 963 5 $Various - (15) Various - Various - Various - (11) Raw sugar Foods Foods Oil of Lemon Trace levels A Trace levels - Trace levels - - A Canned vegetables 0.05-1 45 pg/ml E (brine) Orange juice Trace levels A, E Milk Various levels A Foods and beverages Trace levels A Wet-ash with HNO, F - Discussion of SRMs for quality control - - of foods Review of AS methods - - Direct method. Na, Mg, Ca, Zn by FAAS F Air/C,H, and Fe, Pb, Cu, Al, K, Mn. Sn by ETA-AAS Graphite furnace Evaporate and add S to residue. Ash, A 10 A d.c. mix with graphite powder and excite i n cratered electrode Evaporate (10 g), ash at 550 "C and F - dissolve i n HCI or HNO,, according to technique. Four methods compared P ICP (FAAS, FES, ICP and d.c. arc plasma P D.c. plasma OES) for Ba, Ca, Cu, Fe, Mg, Mn, K, Rb, Na. Zn Values given for Na, K, Ca, Mg, Fe, Cu, Zn, Mn (HGA-2100) Graphite furnace F - Review F - Graphite furnace 1403 1434 '. % 9 9 1438 E 1619 1620 1700 1713 1810 1991

ISSN:0306-1353    

DOI:10.1039/AA9790900187

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

198 Andy tical A tomic Spectroscopy 4.9 BODY TISSUES AND FLUIDS There is growing concern amongst analysts over the reliance often placed on results obtained by the method of standard additions. Although this approach leads to greater confidence in the results, it does not establish accuracy unequivocably, merely the recovery of spikes in a given matrix under stated conditions, The dangers of this approach are compounded if the analyst is not acutely aware of the philosophy behind the experiments he is carrying out, For example, Morrow et aZ. (107) used the method of standard additions to establish their working curve and then used spiking of the samples to confirm the accuracy of the method. This does not necessarily confirm the accuracy, merely the reproducibility of the working curve.It should be emphasized that a given preparation procedure may yield apparently acceptable results by the method of standard additions without liberating all the analyte from the matrix, or by presenting the analyte in a different state, for example a different oxidation state, so that the results are meaningless. In addition, spectroscopic problems such as continuum background absorption or spectral interference remain.If one wishes to confirm the accuracy of a method, it is necessary to analyse the same substrate by two or more entirely different methods; whenever possible one should be a direct approach, e.g., NAA or d.c. arc emission, to avoid extraction problems. CRMs are most valuable in this respect, but there i s a need for these to be prepared for as many materials as possible, preferably from a range of sources.It is also important that the analyst is aware of the technique(s) used for their certification. Recent developments in instrumentation have led to less widespread use of continuous monitoring devices such as chart recorders; increasingly experimental results are read from a stationary digital display or printer read-out. This is much more likely to lead to errors if the system i s not rigorously monitored.These problems are especially likely to occur in AAS using ETA, In a paper by Routh (570), for example, the determination of Cr in urine required considerable attention to a large number of factors in order to obtain acceptable values. Other authors compared two methods of establishing the optimum atomization temperature for Cd (1544).In the first a photocell, calibrated with compounds of known melting point, was used and in the second the normal voltage control method was used. The apparent optimum temperature was 850 "C using the photocell and 18M) O C using the voltage controlled system. With such variations being possible, it i s essential to check all stages of ETA programmes with continuous absorbance monitoring, e.g., on a chart recorder, to ensure no loss of analyte or spurious signals.Assumptions based upon temperatures recommended by other workers may frequently lead to erroneous results. Several reviews were published during 1979, some of which are of particular interest. Tsalev and Razboinikova (414) reviewed the use of AAS for the analysis of blood and serum.Written in Bulgarian, the review contains 129 references, and it would appear well worth the effort of obtaining a translation. Tanaka (1315) reviewed trace metal analysis in a general hospital; this review appears to be of particular interest, because the author claims significant improvements in clinical analysis when using a Zeeman effect AA spectrometer rather than a conventional instrument.Olttaway (672) reviewed developments in AAS and AFS for the analysis of biological materials. Kunc (971) discussed the determination of P in biological samples by AAS and Fazakas (1371) discussed the difficulties encountered in the determination of Sn by ETA-AAS. It is always of interest to observe how well methods compare in accuracy, and collaborative studies have, until recently, been published all to infrequently.Ramelow (658) compared data for his method for Hg in marine organisms with those from 60 other laboratories, and in another publication results were presented for Hg in 353 samples analysed in 5 different laboratories (661). Collaborative results on blood Pb were reported by Boone et al.(1621) and Garnys and Smythe (1 198). Interlaboratory comparisons of CdApplications 199 and Pb in blood (1116) and 12 selected elements in marine organisms (408) were also reported. 4.9.1 Sample Preparation Many papers have been published describing alternative methods of sample preparation for the analysis of clinical specimens. The unwary reader merely searching for an acceptable procedure for a given element may find himself overwhelmed by the multitude of procedures published, each claiming some advantage over the others.On rationalizing the situation, however, he will find that there are really only two distinct opinions, one which says that, for accurate routine procedures, sample preparation must bc kept to a minimum and that direct approaches are the only ones to use, and one which says that direct approaches are the quick route to the wrong result.In reality, both approaches have their place, but in some cases complex procedures are required to produce accurate and precise results. I i general advice can be given, it is to try to find and use the simplest possiblc sample prepara- tion method and rigorously to assess how closely the resulting accuracy and precision mcet the needs of the individual requirement. 4.9.1.1 Methods Involving Minimal Sample Preparation. For a limited number of sample types, no sample pretrmtment at all may be necessary. Routh (1220) determined urinary Cr by AAS after direct injection onto a carbon rod atomizer; the levels detected were ca. 1 ngml-I.Gorsky and Dietz (151) studied A1 in biological samples by ETA-AAS and also found that no sample preparation was required. Serum from 23 unexposed individuals contained 28 2 9pg1-1 Al. The problems associated with sample handling, precision. accuracy, the effect of salts and protein, and the sample relative density were all discussed. Urinary Cd has been determined directly by ETA-AAS (1586).The authors compared the performances of three different instruments in terms of sensitivity, precision, accuracy and detection limit. They found that after suitable optimization of instrument parameters, equivalent performance was achieved on each. Agreement between the analytical results was obtained when the method of standard additions was used. Comparison of the results with those obtained by AFS was said to confirm the accuracy and precision of the AAS procedures. For some samples simple dilution with water ur u suitable reagent suffices. Lo and Christian (709), for example, determined Si in blood, serum, urine and milk by ETA-AAS.The method involved only dilution with water, 14- 1 for blood, serum and milk, and 1 -I- 7 for urine. For lop1 portions the sensitivity was 1.3ng and the RSD was 0.0345.Semen Cu (690.) was determined after 1 : 4 dilution with €€NO,; 10 pl portions were used, and the mean Cu concentration was found t o be 43lpgdl-1. Gold was determined in the whole blood of arthritic patients undergoing Au therapy'(400); after 1 : 20 dilution, 20 pl was analysed using ETA, the RSD being 0.018. Pegon (793) determined A1 in sera (34.1 pg 1-1, RSD=0.035) and cerebrospinal fluid (19.8pg1-1, RSD=0.025) by diluting with an equal volume of aqueous NH, (sp.gr.=O.92) and adding 0.1% Teepol 710; 25 p1 portions were injected into a Massman furnace. Copper has been determined in serum and urine after dilution of thc sample with a solution containing H,PO,, NH,NO, and Triton X-100 (1976).Saeed et al. (1494) determined Se in serum using ETA-AAS. They tried the previously reported use of Ni (see also Refs. 3/35 and 143'1) t o minimize losses and enhance atomization, and found they could ash at temperatures up to 1050 "C. By using Ag for the same purpose, they found it possible to ash at up to 1250 "C without loss. Homogenization i s a simple and rapid method of sample preparation for solid samples for analysis by ETA-AAS provided that the accuracy of the subsequent analysis can bc substantiated. Manganese has been determined in rat livers by acidifying the homogenized200 A 11 a1 y tical A tom ic Spectroscopy tissue with HCl, heating to 60 OC, centrifuging and analysing the supernatant by carbon rod atomization U S ' .No matrix interferences were observed and background correction was found to be unnecessary (1852). 4.9.1.2 Multi-stuge Methods. Much of the published work on multi-stage methods of snmple preparation can be summarized in terms of changes in wet or dry oxidation conditions, in extraction conditions (either the complexing reagent or the solvent being varicd) or in a combination of these. Freinberg and Ducauze (1 11 8) compared various ashing procedures for the determination of Cd and Pb in animal tissues, and Wettern (294) found that digestion with HF/I%CIO, was suitable for determining Pb in marine diatoms.For the determination of Se and Hg in fish, Egaas and Julshann (1047) found it necessary to use HNO,/H,S,O, with a V,05 catalyst; since some selenite was oxidizcd to selenate, reduction with HC1 was necssary belore the hydrids generation step of the AAS determination.The use of tetra-alkylammonium hydroxide for tissue solubilizatioit has again been compared with acid digestion methods (970; see also ARAAS, 1974, 4, 148). The method was satisfactory for small soft samples, but for hard tissues such as bone the solubilizer did not give sufficiently complete digestion and extraction.Solvent extraction is still quite widely used as a separation and /or concentration step. Ishizaki and Ueno (1 48'1) used N-cinnamoyl-N-2,3-xylylhydroxylamine to extract V into CCI, prior to determination by ETA-AAS, Normal complexation /extraction procedures for Au require an oxidation stage to convert any Au(I1) tcr Au(II1). The use of dimorpholine- thiuram disulphide /MIBK was found to render the oxidation stage unnecessary (1052).There has been considerable concern recently about the stability of chelate complexes and several workers now believe back extraction to be essential. Oyamada and Ishizaki (642) found this to be so for Co extracted with trioctylamine into CCl,. There appears to be increasing interest in precipitation of the unalyte before analysis, either directly or after dissolution.Pickett et al. (1 12) described this approach, but one fecls that quantitative collection of the precipitate might cause problems in routine use. Nichols and Woodriff (553), however, used the same approach but filtered the suspension through a porous graphite crucible, which retained the precipitate and was suitable for insertion into ETA devices.It is generally beneficial to add a small amount of co-precipitant if quantitative recoverics are to be obtained. 4.9.2 Atomic Absorption Methods Issaq (1706) studied interference eflects in the determination of Cd, Pb and Zn in biological samples using ETA. He found that the matrix, ashing temperature and digestion reagents could all affect the results drastically, and hence that all three factors should be explored rigorously both independently and in combination.In some instances the method of standard additions was required, but it was strcssed that it should only be used after the analyst had satisfied himself that it was indeed a satisfactory approach to a particular problem. Koirtyohann et aE. (104). took up the particularly important point of the need for morc generally applicable proccdurcs for overcoming matrix interferences.They studied several matrix modifiers and M o treatment of furnace tubes for the determination of Cd, Cu, Fe, Ni and Pb in blood, urine, process waters, natural waters and digested tissues. Suzuki et al. (500) found interference effects in the FAAS determination of Co could be reduced by the addition of oxine to the sample solutions.Berndt and Jackwerth (18089 used discrere sampling to dctcrmine Cu, Fe and Zn in serum by FAAS. A 50Opl sample of serum was sufficient to determine all three elements. Under suitable conditions 25 pl of serum was sufficient for Cu and Zn. Uchida and TidaApplications 20 1 (160) also uscd a discrete nebulization method, although they used a Teflon funnel attached directly to the nebulizer, an approach that has two disadvantages. First, the funnel does not have a continuous flow of water passing through it, and so the nebulizer may be more prone to blockage, thus reducing one of the major advantages of discrete nebulization.Secondly, such funnels are particularly susceptible to picking up airborne contamination.Micro- sampling cups, of the type supplied with autoanalysers, may be purchascd complete with lids and, if used as normal but small sample containers, overcome these problems. More and more changes are being made both to basic AA spectrometers and to the atomizers used with them. Robinson and Weiss (741) described an r.f.-heated carbon-bed atomizer for the determination of Cd in whole blood.Nichols et al. (457) significantly reduced background absorption during the direct analysis of solid biological samples by the use of a graphite crucible sealed with a graphite lid in a constant-tempzrature furnace. It was claimed that the lid acted as a trap for smoke particles but was permeable to analyt:: atomic vapour, Modification of graphite atomization surfaces by coating, the use of metal collars or liners, or by the use of metal tubes is becoming increasingly common. Baily et al.(1233) found a W-coated tube particularly useful in their studies of trace metals in biological ma teria Is. Chakrabarti et al. (1995) have dcscribcd the design and performance of an ETA hzatcd rapidly by capacitive discharge.The pyroiytic graphite tube atornizzr wns heated ai r a t s up to 100 K ms-1 by capacitive discharge to produce temperatures up to 33008K. It was claimed that the atomizer i s interference free, only one standard in ultra-pure water being required. Background correction with simple single-lamp systems is difficult at wavelengths above 30Qnm because of low source intensity. Thus Cr, with its primary resonance line at 357.9nn-1, often presents a problem. Kayne ef al.(1151) overcame this by replacing the D2 lamp assembly in a Perkin-Elmer 603 by an air-cooled 100 W tungsten-halogen lamp and a mirror; Cr was then detected down to 54ng1-1. Reports of the practical application of Zeeman effect spectrometers to biological samples are now becoming widespread (1 70, 612, 909, 910, 1245, 1528, 1785 and 1973) and some of these studies claim thzt the method has significant advantages over conventional AAS.Veillon and Wolf (182, 969) and Wolf et al. (163, 1412) have described the use of a continuum-source, echclle monochromator wavelength-modulated AA spectrometer for the determination of Cr in biological materials. Incrcasing attention is being paid to the nature and flow rates of gmes in electrother-ma1 atomizers.Fazakas (1006) introduced air into a furnace during the charring stagc and found it hclped to minimize background absorption and prevent carbonaceous deposits. Carc is required if tube life is not to be seriously impaired. Steiner and Moy (1000) discussed in considerable detail the use of various purging gases in ETA.Hydride generation techrtiques are now used routinely but some novel modifications have been reported. In the determination of As, Wolz and Mclcher (1980) suggested adding Antifoam IOOA Emulsion mow-Corning) to thc reduction cell to prcvent Ioarning. Rigin (1835) has studied thc use 01 electrolysis to reduce Sn to SnH, prior to decomposition in a T-shaped quartz atomizer heatcd at 7004 "C, Two teams have suggested the use of optically monitored stable isotope dilulior: atzalysis (769, 1550).This technique exploits the separation of the resonance lines of GLi and 7Li. Separate HCLs are used, with pure cathodes made from each isotope, to dcterminc the isotope ratio by AAS. Atomic absorption spectroscopy has been used as a detector in various chromatographic separations.Elcctrophorcsis /ETA has been used to scparate protcin fractions and dcterminc’02 Analytical Atomic Spectroscopy their Cu content (1871) and ion exchange/ETA was used for the measurement of Cd in bone (786) and Cu in amino-acid complexes in human serum (436). Molecular exclusion chromatography has been used with FAAS for estimation of the molecular mass distribu- tions of metal compounds in blood from patients with anaemia (214) and with ETA to study Cd, Cu and Zn in human parotid saliva (1466).FOT the determination of alkyl Hg com- pounds in fish tissue GC/ETA was used (1463). 4.9.3 Atomic Fluorescence Methods The number of papers appearing recently on AFS has increased significantly. The technique has been used for the determination of Ca and Mg in serum, using an IDES system (1659), and for the determination of Hg in biological materials, using a non-dispersive instrument (34, 1157).The determination of Cd in blood and urine has been described (1177) and the applications of FAFS in clinical analysis reviewed (936). Some applications of continuum sources in AFS have been reported. A 300W Eimac xenon arc lamp was used for the determination of As, Se and Sb using a non-dispersive instrument and the hydride generation technique; the hydrides were concentrated by freezing in a U-tube and separated by GC techniques to allow sequential multi-element determinations on a single sample (5733.A continuum source has also been used for the trace element analysis of blood (413). 4.9.4 Emission Methods Numerous applications papers have been published on the use of inductively coupled plasmas. Steiner and Boumans (878) reviewed trace element analysis of biological materials using ICP-AES and Annett and Bearse (563) discussed the applicability of the ICP to tracc element determinations in blood. Haas and co-workers (705) studied the application of ICP-AES to the simultaneous determination of trace elements in urine samples, but found that the technique could not detect many of the metals directly at normal levels.Barnes and Genna (1546) used ion exchange followed by ICP-AES for the determination of trace elements in urine. When a concentric pneumatic nebulizer was used with an ICP, detection limits for A1 of 1 pg 1-1 in urine and 4 pg 1-1 in blood were claimed (1853).For 13 “healthy” subjects ICP-AES gave Ba levels of 4.3pg1-1 in urine and <1 pgl-1 in blood (1492). Boron in whole blood has also been determined (1435). Hubert and Bellavance (739) used an ICP and an echelle monochromator to analyse biological materials. An integrator for use with a simple flame photometer has been reported, which improved detection limits 10-fold for K (691); there were also two papers on conventional spectrographic methods (755, 1822).Thc d.c. arc plasma has yet to emerge as a successful routine analytical tool; however, Skerten (618) published a paper describing the use of flow injection methods with such a system. Low power microwave pZmmas are generally regarded as being of rather limited value for the analysis of biological materials.Nevertheless, two papers on the use of MIPS have been published (146, 1553), and Jutte et d. (1966) reported the use of sealed MIP-AES. 4.9.5 Comparisons of Methods Lo and Coleman (474) compared the results obtained by ETA-AAS with those obtained by colorimetry, for the determination of As in animal tissues, and found that they agrecd well. Ward et al.(1579) compared NAA, conventional AAS and Zeeman effect AAS for the determination of trace elements in whole blood; other workers compared the results of serum analysis for Na using ion-selective electrodes and flame photometry (1971). Raie and Smith (4’66) compared thermal NAA and ETA-AAS for the determination of Se in biologicalApplications 20 3 materials and found little difference in accuracy and precision between the two methods; they concluded that a choice should be made on the grounds of urgency and convenience.A comparison has been made of GC and AAS for the determination of N a D X in human serum and urine (674). The use of AAS has been compared with that of a Technicon AutoAnalyzer for the determination of serum Fe (1221). Agreement was good above 40 p g ml-1, but unsatisfactory below 20 pg ml-I.Table 4.9 BODY TISSUES AND FLUIDS €i P Element h/nm Matrix Concentration Tech.Sample treatment Atomization Re?. Form A1 309.3 Biological samples 20-40 ng/ml At 309.3 Biological fluids pg/l levels (serum) Al A1 As As As A8 As - Blood 396.1 Blood, urine - Biological materials - Biological materials - Hair - Biolog i ca I mater I als 193.7 Animal tissues Trace levels 30-50 ng/ml Trace levels (0-200 ng absolute) Trace levels 0-02 fig level (absolute) Direct furnace injection for samples of Graphite furnace 151 Dilute (1 : 1) with NH,OH and add 0.1% Graphite furnace 793 Teepd 710.Take 25 I portion, dry at 120 "C, ash at 1700 'C and atomize at serum, plasma, urine (HGA-2000) 2aao c - Graphite furnace 1329 Dilute with H,O P ICP 1853 Modification of ASH,-evolution method, Heated SiO, cell 34 using AFS Tissue samples-Dry-ash at 550 "C Graphite furnace 162 with addition of Mg(NO,), solution.Dissolve in 10N HCI, add KI, extract with CHCI, and back-extract with Mg(NO,), solution Urine-Absorb sample on cotton, air-dry for 2-3 days, combust i n 0,-flask and proceed as in (A) Wet-ash with HN0,/H,S0,/H,02, dilute, F - 352 reduce with NaBH, and pass ASH, to flame in argon stream $ Method for speciation of organic-As, F - 354 2 2. 2 inorganic As( I l l ) and As(V). Solubilize sample in 6N HCI, extract As(ll1) with 5' 2 L s HNO,/H,SO,/H CIO, b B toluene and As(V) similarly after reduction with KI. Organic-As i s retained in HCI. Backextract toluene phases with H,O.For analysis, digest solutions with Add 1 . 5 g MgO 4 10 g cellulose powder Graphite furnace to 5 g tissue sample, char until fumes (HGA-2101)) cease, add 1.5 g Mg(NO,),.GH,O and ash at 550 "C. Dissolve residue in HCI 474 2 13 zAS - Biological samples A8 As As As Au Au Au - Urine, faeces - Urine - Urine 193.7 Urine 242-8 Blood - Blood, plasma, tissue 267.6 Serum. urine B - Blood Ba 233-5 Biological material (viscera) Ba 455.4 Urine, blood From 2 ng (absolute) F From 5 ng (absolute) A Trace levels A 50-200 ng/ml A ng/ml levels A 5 pg/ml levels A A - 0.4-23 pg/ml A 0.1-1.0 pg/ml E mg/g levels E ( i n ash) < 1-260 ng/ml E (blood) 4-280 ng/rnl (urine) G G G L G L L L L S L Non-d ispersive continuum source AFS F Ar/Air/H, method. Reduce acidified solution with or NaBH,, trap hydrides of As, Se and Sb in N,/Air/H, liquid-N, U-tube and sweep with argon or N, to flame Mix with Mg(NO,),/MgO ashing aid, dry and ignite to 500 "C.Dissolve residue (970 "C) in 6N HCI. Add NaBH, and sweep ASH, in N,/H, flow Digest with HNOJHCIO, ( 1 : 1). Reduce Heated SiO, tube with NaBH, and dry ASH, with conc. H,SO, trap before introduction to atomizer Hydride-generation method.To 10 ml of 1.5% HCI in reaction vessel add 0.5 ml urine + 1 ml 1 YO AntifoamllOA solution. Reduce with 3% solution of NaBH, in 1 O/O NaOH. Calibrate by standard addition method Dilution only ( 1 : 19 with H,O) Graphite furnace Study of effect of gold therapy on Au, Graphite furnace Cu, Zn levels Serum-Treat with HCIO, + Triton X-100 Graphite furnace + MlBK + dimorpholinethiurarndisulphide (HGA-76) (chelating agent). Shake and centrifuge.Analyse MlBK fraction Urine-As for serum, omitting Triton X-lo0 add I tion Digest with HNO, i n PTFE pressure P ICP vessel. Dilute to volume (10 ml for an original 1 ml whole blood sample) Ash at 650 "C and mix 10 mg ash with 45 mg graphite + 45 mg Li,CO, -I- 22-5 pg Be (internal standard). Use Be 234.8 nrn reference line Dilute blood 1 + 9 and urine 1 + 3 P ICP Heated SiO, tube Hydride-generation method - - Heated SIO, cell (900 "C) A 5 A a.c. 573 % -. 2. g Gl 1080 1329 1491 1980 400 965 1052 1435 755 1492Table 4.9 BODY TISSUES AND FLUIDS-continued Form ch E I e ment X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Be 234.8 Urine, faeces, hair, nails ng levels (absolute) A 1-25 ng/ml (in extract) Bi Ca Ca Ca Ca Ca Cd Cd - Blood - Biological samples - Dental plaque 422.7 Urine 422.7 Serum - Serum - Urine - Blood, urine From 2.4 ng/ml A - A 100 ng level E (absolute) Cd - Blood, urine pg/l levels A Cd - Fish tissue pg/g levels A Cd 228.8 Sea-water clams ng/g levels A (shells and organs) or above L G L s L L L L L L L L L Digest with HF/HCI/HGIO,, evaporate (General method, with variations according to type of sample) Digest with HNO, at 180 "C in PTFE pressure vessel.Cool, add urea and re-heat lo 180 "C. Shake with HCI and add NaBH, to generate BiH, - Graphite furnace Dissolve in HCIO, to give final volume P D.c. argon of 500-1000 and take 100 aliquots plasma for Ca, Mg determinations Prepare samples and standards in F N,O/C,H, aqueous diluent (51 mmol KCI) to suppress ionisation interferences. Pulse-nebulize 50 &I sample aliquots Computer-controlled dual wavelength F - system.(For Ca, use Sr internal standard) Graphite furnace and redissolve with addition of La. (HGA-2100) Heated SiO, cell (800 "C) - F - - F - Heat with HNO,/H,SOJH,O,, evaporate F - to fumes, dissolve residue in formate buffer containing ascorbic acid + 1 ,l@phenanthroline and extract Cd with HMA-HMDC into mixture of xylene + di-isopropyl ketone Treat with HNO,.Use ramp-mode heating Graphite furnace and atomize at 1500 'C for Cd or 2400 "C for Pb Eleven species analysed for Cd and Zn F - Digest with HNO, and extract Cd with DDC/d i-is0 b u ty I ketone Graphite furnace Graphite furnace 1044 779 426 61 8 1229 455 I659 114 388 $ Y, 5. 2 5 613 2. h x 663 5 692 $ 2b Cd 228.8 Whole blood - A L, S Add 1 of EDTA-treated blood to carbon Graphite furnace 741 or filter-paper disc (pre-treated with % -. HNO,) and atomize in RF-heated cell. Calibrate with aqueous Cd (NO,), solutions 250 "C and dissolve residue in citrate medium (pH 9). Extract with dithizone into CHCI, to remove Pb, Cd, Zn and back-extract with 1M HCI.(A separate procedure is used for Sn) 0, G* Cd - Eiolog ica I materia Is Trace levels A L Digest with HN0,/H,02, evaporate at Graphite furnace 776 $ Cd Cd Cd Cd Cd Cd Cd Cd Cd - Bone - Blood, urine - Bovine liver 228.8 Blood, urine 228-8 Blood, urine - Bone 228.8 Parotid saliva 228.8 Urine 228.8 Urine 10-100 ng/g - Trace levels 1.5-8 ng/ml 0.2-25 ng/ml 10-1 00 ng/g A L Wet-digest with HNOJHCIO, transfer Graphite furnace 786 to Dowex 5OW-X8 column and elute with 0.5M HCI determination in reference samples 650 "C (0-2 rnl at pH 5) with APDC/MIBK.Inject into furnace, dry at 150 "C, ash at 450 "C (Cd) or 350 "C (Pb) and atomize at 18QO "C (Cd) or 2400 "C (Pb) centrifuge and aspirate as CaSO,, by addition of H,SO,, and separate P as NH4 phosphomolybdate complex.Extract Cd with DDC into MIBK A L Inter-laboratory (5) study of Pb and Cd Graphite furnace 1116 A L Digest wilh H,SO, (1 : 3) and ash at F - 1118 A L Shake blood (0.1 ml + H,O) or urine Graphite furnace 1152 F L Dilute with 0-2M HCIDriton X/H,O, F Air/C,H, 1177 A L Separate Ca from bone digest solution Graphite furnace 1260 0.5-17 ng/g A L Cd/Cu/Zn-distribution study.Fractions Graphite furnace 1466 separated by gel filtration From 0.05 ng/rnl A L - Graphite furnace 1544 ( HGA-2000) A L Comparison of 3 commercial ETA-AAS Graphite furnace 1586 i nslrurnents (SP 9-01, CRA-90, HG A-72) Cd 228.8 Serum A L Study of matrix effects Graphite furnace 1706 1 3 ( HGA-2000) 0t d 50 Table 4.9 BODY TISSUES AND FLUIDS- continued 0 Element X/nm Matrix Concentration Tech.Sample treatment Atomization Ref. Form Cd 228.8 Blood, urine c o c o c o co c o 240.7 Biological materials 240.7 Biological samples 240.7 Blood, urine 5-30 ng/ml A L (A) Blood-Mix 10 sample with 10 Graphite furnace 1974 1% (NHJ2HP0, solution, dry at 1OD " C and ash at 300 " C ( 5 ) Urine-Mix 10 sample with 10 1% NH,F solution, dry at 100 "C and ash at 300 "C (See also Pb, ref. 1974) (4- microboat) 0.1-0.7 pg/ml A L Add saturated oxine solution to F Air/H, 500 ( i n extract) overcome interference effects + AI,O, absorption ng/g levels A L Ash at 550 "C, dissolve in HCI and Graphite furnace 642 cell extract with trioctylamine into CCI,.Back-extract with H,O dryness, add HNO,, evaporate, add HCI, evaporate (x2) and dissolve i n 9M HCI.Pass through ion-exchange column (Dowex l-XS), elute with 4M HCI, evaporate to dryness and finally dissolve i n 2 rnl 0.01M HCI 0.1-20 ng/ml A L Digest with HN0,/H2S0,, evaporate to Graphite furnace 714 (HGA-74) - Bovine blood p l a m a - A L - Graphite furnace 1006 - Blood 0.1 ng/ml or above A L Ash at 550 "C, dissolve in 10N HCI, Graphite furnace 1261 solvent-extract with 5% trioctylamine and back-extract with H,O ( 1 rnl for original 5 ml sample) b % 1 pg/l level A L Direct method; 50 sample Graphite furnace 169 0 2 b s technique for Cr, with parallel verification by AAS method 3 (HGA-74) b - 3.Cr - Urine Cr - Biological materials Trace levels A L Description of stable isotope dilution F - 182 A L - Graphite furnace 268 ? Cr - Serum, plasma nrnol/l levels Cr - Urine 1 ng/g levels A L Study of analytical parameters Graphite furnace 570 3 Cr - Biological samples Trace levels A L Application of wavelength-modulated Graphite furnace 969 5 continuum source echelle monochromator 0 c- ETA-AAS system 0CI 9L6 1 688 L CL8 L 808 1 0P9 1 9991 LLEL S96 069 9EP PEP 9 LP 68E 8 16 P!Z ELL 9E61 ZCPL OZZL .h, m. 2 ,". LSLC 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 n3 "3 "3 - V - VTable 4.9 BODY TISSUES AND FLUIDS-ccorzrittued 2 0 Element X/nm Matrix Concentration Tech* AnalyLe Sample treatment Atomization Ref. Form - Blood - Cuttlefish - Serum - Blood - Serum 253.7 Biological materials - Fish tissue - Dental pulp - Biological samples - Bi 01 og ical products ; vaccines - Fish tissue - Fish tissue 253.6 Urine - Teeth, jawbones 253.7 Fish tissue - Fish tissue - pg/ml levels - cLg/g levels (hair) ng/g levels (placentae, teeth, bones) 10-100 ng (absolute) A A A A A A A A A A A A A A A A L L i L L G G L G G G G (3 G G G See Cu, ref. 214 F - See Cu. ref. 389 Graphite furnace - F - See Cu, ref. 1808 F - Digest with HNO, Cold vapour Oxidize with HNO,/H,SO,, for total Hg determination (deals primarily with radiochemical method for methyl-Hg) - Graphite furnace Comparison of GC and AAS methods for determination of organo-Hg compounds Digest (cold) with H,SO,/KMnO, prior to Hg evolution.(Method for mercurial preservalives) - Cold vapour Survey of results from Italian official Cold vapour enquiry (365 samples, 53 species) Prepare standards from (stable) stock Cold vapour solution of 0.5 gg/ml of Hg( I I ) in Clean with 10% H,O,, homogenize in agate mill and dissolve portion (20-200 me) in HNOJHF in PTFE cell at 180 "C.Cool, add H,BO, and continue by cold vapour method See Se, ref. 1047 Digest with H,SO,. Reduce with Sn( I t ) / Cd( I I ) reagent and aerate to determine inorganic and phenyl-Hg. Add NaOH and aerate to determine methyl- and ethyl-Hg Cold vapour Cold vapour Cold vapour 0.3% HCI Cold vapour Cold vapour Cold vapour 214 389 1221 1640 1808 149 302 401 41 0 439 660 661 756 5 Q .1" 768 $ 1047 s 3 6' 1048 2 2 a Y .51Hg - Biological materials ng/g levels (fish tissue, food, water) 253.7 Fish tissue 2 ,&g level HQ K K K K K K K L i L i L i - Biological samples 253.7 Fish tissue 253.7 Hair.fish 253.7 Fish tissue - Blood 253-7 Fish tissue - Biological materials - Biological samples - Biological fluids - Serum - Serum - Body fluids - Serum, plasma - Rat brain - Biological samples 670.8 Serum From 0.3 pg/g - up to 5 p9/9 From 1 ng (absolute) From 2 ng/g (as methyl-Hg) 0.1-1 @g/ml - - - 3.5-5.0 mmol/l 10-100 ng (absolute) - - F A A A A A A A E A E E E E E A A E G G G G G L G G L L, s L L L L L L L, s L Deposit Hg on Au cathode by electrolysis Heated SiO, tube of sample i n medium of 2M Li,SO,/O*lM HNO,.Heat electrode at 700 "C and sweep Hg. ,in helium, to heated cell irradiated by U.V. lamp Digest with alkali, distil into K,S,O, solution, acidify and digest on steam bath. Measure (organic) Hg by cold-vapour procedure Burn ,in air and collect Hg in cold trap for cold-vapour AAS analysis GC/AAS method (alkyl-Hg compounds) - - Digest with HNO, followed by H,SO, + KMnO,.Add NH,OH.H,SO, + NaCl Homogenize, extract with acetone and treat with acid Cu( I I) bromide/toluene/ dithizone. Atomize at 950 "C Treat with alkaline NaBH, Homogenize in H,O, add NaCl + HCI and extract with toluene. Back-extract with cysteine acetate, oxidize with H,SO,/KMnO, and reduce with SnCI, Add Li (20 pg/ml) to both samples F - and standards - Graphite furnace flame photometer Cold vapour Cold vapour Cold vapour Graphite furnace Cold vapour Cold vapour Description of improved-sensitivity F - Pulse-nebulization method F - Development of reference method F - Review { 8 refs.) F - - F - - Graphite furnace - Graphite furnace bLi stable-isotope determination applied F - to p har maco kinet ic studies 1157 & 5 E. 2 7 1189 1219 1463 1667 1 702 1900 1931 372 426 691 1763 1807 1918 1971 406 426 769 1 3 eTable 4.9 BODY TISSUES AND FLUIDS- c.orilinued 23 P-) Element A/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form - Li Mn M n Mn Mo A Blood platelets - L Serum 5-1 0 pg/m I A L Biological samples - A L, S Dental plaque 100 ng level (absolute) E L Urine Serum A L A, F L Biological samples From 0.5 p g / I A L (blood) - Dental tissues 279.8 Animal tissue 279.5 Blood, serum - Biological materials Mo - Na - Trace levels A L A L A L E S Urine, serum, erythrocytes Trace levels A L Serum 11 S159 mmol/l E L Separate platelets on Millipore filter, F - disrupt ultrasonically and determine L i in extract None F - Graphite furnace See Ca, ref. 618 P D.c. argon plasma See Ca, ref. 1229 F N,0/C,H2 ( A ) Whole blood-mix (1 : 4 ) with 0.1% Triton X-100 and take 10 I P. aliquots. Ash at 350 "C and atomize at 2500 "C ( 6 ) Serum-as in ( A ) , but wiih (1 : 1) or (1 : 4) dilution as necessary. Take 15 aliquot and use ramp-heating mode - - F - Graphite furnace Graphite furnace Digest with HCI at 60 "C and centrifuge Graphite furnace Mix 250 sample with 750 I Triton Graphite furnace X-100 (1 g/l).Take 10pl aliquots. Atomize at 2400 "C Ash 20 g sample at 5MF-6[)10 "C, dissolve - - in HNO,, add H,O, and evaporate to dryness. Dissolve i n HCI, filter, dilute to 200 ml and add ascorbic acid + thiourea, followed by 50% NH,SCN solution and 0.005M chromopyrazole solution in 1N HCI.Filler, wash and mix precipitate with graphite/GeO, mixture ( 3 : 1 ). Wet-ash with H,SO, and determine Mo, W in ash - Graphite furnace Dilute ( x100- x200).1nter-laboratory F - study of proposed reference method - (CRA-63,90) P 1218 1550 426 618 1229 1659 61 2 1238 1852 1973 5 6 435 $ : s a h 3 K' 2 707 2 325 2 GYNa Na Na Na Na Ni NI P P Pb Pb Pb Pb Pb Pb Pb Pb Pb - Biological materials - Biological materials - Serum - Body fluids - Serum, plasma - Biological materials - Fish tissue, shellfish - Biological samples - Biological tissue (Mo) (V) - Urine - Marine diatoms 283-3 Blood - Blood, urine - Biological materials - Whole blood, serum - Serum - Biological tissues - Blood, urine - 137-144 mmol/l 0.3-1.5 mg/l 0 . 1 pg/g levels - ng levels (absolute) 6-31 ng/ml 150 p g / l level 44 p g / g pg/I levels Trace levels Trace levele 10-30 pg/l E A E E E A A A A.E A A A A A A E A A L L, s L L L L L L L L L L L L L S L L See K, ref. 372 F - - Graphite furnace See K, ref. 1763 F - See K. ref. 1918 F - - F - Dry, wet-ash with H,S04/HN0, ( 1 : 5), F - stand (24 h) and add H,SOJHN03/HCI0,. Heat to white fumes, add further acid mixture.heat until clear, dilute with H,O. filter and make up to volume Freeze-dry and ash at low temperature F Air/C,H, Review of operating parameters F - Graphite furnace Separate P as molybdovanadophosphateF N,O/CIH, complex and determine eilher Mo or V, according to P level Graphite furnace - F - Wet-ash with HF/HCIO, Graphite furnace To 2 ml heparinized blood sample add F - 4 ml formaldehyde 3- 2 drops Triton X-100, followed by DDC 4- MIBK. Mix for 10 min, centrifuge and measure Pb in MIBK phase See Cd, ref. 613 Graphite furnace See Cd, ref. 776 Graphite furnace Study of Zeeman-effect background F Air/qH, correction in comparison with alternative Graphite furnace systems Dry, ash by microwave plasma asher, P Microwave- dissolve and extract Pb by chelate] excited solvent.Back-extract into aqueous sealed tube solution, add excitation buffer, freeze-dry and seal in quartz tube in H, Digest with HNO,. (Study of factors See Cd, ref. 1116 Graphite furn.ace Graphite furnace affecting furnace tube life) (HGA-76B) 372 426 $ 1763 $. 1918 *, 1971 673 1075 971 369 114 294 444 61 3 776 909 966 1056 1116 2hJ P Table 4.9 BODY TTSSUES AND FLUIDS-continued - Element A/nm Matrix Concentration Tech* Sample treatment A torniza tion Ref.Form Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pb Pt Sb Sb - Bovine liver - 283.3 Blood, urine 15D-480 ng/ml - Blood, blood digest, - - Blood - - Blood - saline, water - Blood 0.684'93 yM/% 217.0 Serum - - Blood - Blood, urine - Tartar 217.0 Blood, urine 265.9 Albumen 304.2 - From 3 ng/ml From 3 yg/ml (in extract) 50-550 ng/ml (blood) 5(1-3(yo ng/ml (urine) Various levels - Biological samples From 15 ng (absolute) - Urine 0-12 rug/rnl A A A A A A A A A A A A F A L L L L L L L L L L L S G L See Cd, ref. 1118 F - 1118 See Cd, ref. 1152 Graphite furnace 1152 I nter-laboratory study - - 1198 Application of W-coated graphite tube Graphite furnace 1233 Discussion of factors involved in Graphite furnace 1316 develop me nt of reference rn e t hod Inter-laboratory (113) study.Comparison F - 1621 of 5 AAS procedures with ASV and isotope-dilution MS Graphite furnace See Cd, ref. 1706 Graphite furnace 1706 (HGA-2000) Review (9 refs.) F (Delves Cup) 1784 Zeeman-effect method Graphite furnace 1785 Dissolve in HNO,, adjust to pH 4-5 Graphite furnace 1786 with NH,OH and dilute (A) Blood-Mix 2 blood with 25 Graphite furnace 1974 1% Triton X-100, dry at 100 "C, ash at 500 "C (6) Urine-Mix 10 1 YO NH,NO, solution, dry at 100 "C and ash at 350 "C (See also, Cd, ref. 1974) urine with 10 % ;i' 800 "C, dissolve residue in HCI/HNO, (HGA-72) b 5 3 G' See As, ref. 573 F - 573 % 2 industrial hazards associated with 2 Dry and take 10 mg sample. Ash at Graphite furnace 1031 ' (3 : l ) , evaporate and redissolve in 10% HCI.In furnace, dry at 40 "C, ash at 1500 "C and atomize at 2600 "C t/, Aspirate sample directly. (Study of F - 1133 S b, 0,-con t ai n in g p i g m en t 0Sb 287.8 Blood 1 ng/rnl level Sb 217.0 Biological samples l & l O O ng/g Se - Kidney cortex From 10 ng/g Se Se So Se Se - Blood, urine 196.0 Biological material - - Biological materials Bi olog ica I sam p les 196.0 Fish tissue pg/l levels 1-2 pg/g (human liver, dry weight) From 9 ng (absolute) ng/g levels ng/g levels (dry sample) Se 196.0 Serum - se - Biological samples - E A A A A F A A A A L G L L, G L G G G L G Ash 1 rnl sample in microwave-excited P MIP 0-plasma and dissolve in 0.1M HCI. Extract Sb, Te with DDC/tetrachloro- methane and back-extract with Cu( II)/HCI solution.Prepare sealed EDL with 100 sample solution 3- Bil,/Cs or K I buffer, at 2.5-5 Torr H, Digest with HNO,/H,SO, until clear, add H,O,/HNO, (1 : 1) dropwise, evaporate to low bulk (0.1 ml) and dilute to 2 ml with 1M HCI. Add 10 ml H,O, 1.5 ml of cornplexing agent (NaEDTA + ascorbic acid + KI) and 2 ml lOM HCI. Reduce with NaBHJNaOH and pass SbH, to furnace Lyophilize and dissolve in HNO,.Dilute x 10 for analysis, using standard addition method of calibration, with 10,Jl aliquots. Alomize at 2900 "C Comparison of hydride-evolution (preferred) and ETA-AAS methods Freeze-dry at -35 "C (Comparison with NAA method) Heated SiO, cell Graphite furnace Heated SiO, cell Graphite furnace Graphite furnace See As, ref. 573 F - Digest with HNO,, evaporate and ash F OJH, with addition of Mg(NO,),.Re-dissolve and add NaBH, to HCI solution Grind, freeze-dry, homogenize and digest Heated SiO, cell with HNO,/H,SO, + 0.1% V,O,. Boil, add few drops H,O, and cool. Separate into 2 aliqots. For Se, add HCI followed by NaBH,. For Hg, add KMnO,, followed by NH,OH.HCI + SnCI, Add Ni solution to avoid Se ashing losses.Calibrate by standard addition method Study of interference effects in hydride- generation method, using NaBH, ( f- quartz cell) Graphite furnace (HGA-76) Heated cell 4 1553 'c- 0' 2. % 2 1638 170 387 446 573 967 1047 1494 1893 p.,Table 4.9 BODY TISSUES AND FLUIDS-continued !2 Q'r Element X/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form SI I Blood, serum, urine Si - Blood Sn - Biological materials Sn - Biological materials Sn Te V V V W Zn Zn Zn Zn Zn Zn Zn 286.3 Biological materials 238.6 Blood - Fish tissue, shellfish - Blood 318.4 Biological materials - 6iological materials - Human saliva - Blood - Biological fluids - Rat tissue - Skin - Fish tissue - Biological materials 1.3 ng level (absolute) 1 pg/ml level Trace levels - 1-100 ng (absolute) 0.25 ng/ml 0.1 pg/g level From I ng/ml (Average level 5.8 ng/ml) 10-80 ng/ml (in extract) Trace levels - - From 0.5 mg/l Trace levels 10-50 ng (absolute) UP to 820 pS/S Trace levels A A A A A E A A A E A A A A E A A L L L L L L L L L S L L L L L L L Blood, serum-Dilute (1 : 1) with H,O Urine-Dilute (1 : 7) with H,O Calibrate by standard addition method Graphite furnace Graphite furnace Graphite furnace Graphite furnace - - Digest with H,SOJHN0,/H202 and extract Sn, as iodide complex, into to I uene (See also Cd, ref. 776) Electrolyse in KOH medium, with Pt anode and Pb cathode. Pass evolved SnH, in stream of argon to atomizer at 700 "C See Sb, ref. 1553 P MIP See Ni, ref. 1075 Wet-ash with HNOJHCIO,, treat with KMnOJH,SO, and extract with N-benzoyl-o-tolylhydroxylamine into CCI, Digest with HNOJHCIO, dilute with H,O, Graphite furnace add 0.02M KMnO, dropwise and extract with N-c i n nam oy I-N-2,3-xy ly I hyd r oxyl- amine into CHCI,, with addition of HCI.Determine V in CHCI, fraction See Mo, ref. 435 Heated cell Graphite furnace Graphite furnace (GA-2) - - - F - See Cu, ref. 214 F - - F - See Cu, ref. 434 F - Dissolve in HNO, to give final volume of 200-500 and take 100 aliquots for plasma injection. See also Ca, Mg, ref. 618 P D.c. argon See Cd, ref. 663 F - See Cd, ref. 776 F Air/C,H, 709 1368 266 776 1835 1553 1075 1257 1481 b -2 435 : 113 2 214 416 2 434 3 s* 61 8 .x" 2 663 776 2Zn Zn Zn Zn Zn Zn Zn Zn TETD (indirect) - Blood, plasma, tissue - A - Rat liver, bone, serum Trace levels A - Hair, blood, saliva Trace levels A 213.9 Parotid saliva 5-63 ng/g A A 213.9 Serum - - Serum 1 pg/ml level A - Serum 0-6 Irg/ml level A - Serum 324.7 Serum, urine (CU) A - ng/l levels A Various - Blood, urine, tissue (5) Various - Fish tissue (6) Various - Biological materials Various - Blood (5) Trace levels ng/g levels Trace levels Trace levels A A A E L L L L L L t L L L L L G See Au, ref. 965 F - Bone, liver-Dry at 105 "C, ash at F Air/C,H, 450 C", evaporate with HNO, and dissolve in HCI Serum-Treat with HNOJHCIO, (Dietary study) See Cu, ref. 1317 F - See Cd, ref. 1466 Graphite furnace See Cd, ref. 1706 Graphite furnace (HGA-2000) Graphite furnace ( CRA-63) Take 1 450 "C and atomize at 1400 "C sample, dry at 130 "C, ash at Graphite furnace See Cu, ref. 1808 F - Method for detection of tetraethyl- F Air/C,H, thiuramdisulphide (TETD) via formation of NaDDC, in drug overdose analysis.Treat 2 ml urine sample with buffer (pH 4) + excess Cu( II) solution. Extract Cu chelate with CCI, Study of matrix interference problems in ETA-AAS, with reference to Pb, Cd, Ni, Cu, Fe Graphite furnace Dissolve sample with 25% ( m / V ) solution Graphite furnace of tetramethylammonium hydroxide in (HGA-2000) methanol.Calibrate by standard additions method. Elements : Cd, Cu, Cr, Ni, Pb, Zn Application of carrier-precipitation Graphite furnace technique, using APDC + Fe or Co as added carrier metal Mix blood (1 : 6) with acid mixture P Microwave (HNO3/H,SO,/HCIO,--4 : 4 : l ) , heat and dilute to approx. 2N acid level. Proceed by hydride-generation method to determine Ge, As, Se, Sn, Sb (Ar/He) b 965 2 2. 9 z 1038 2 1317 1466 1706 1762 1806 iaoa 674 104 1 07 112 146Tablc 4.9 BODY TISSUES AND FLUlDS- coizliizued N - Element A/nm Matrix Concentration Tech. Form !Sample treatment Atomization Ref. Various (7) Various ( 8 ) Various Various Various Various Various Various (5) ( 6 ) (12) Various (7) Various Various (9) Various (8) Various ( 6) Bovine liver Trace levels E, A L Decompose sample with HNOJHCIO, i n F - B I o log ic a I sam p les A Serum, urine Trace levels A Bacillus subtilis Trace levels - Bovine blood - A Oyster tissue Trace levels A Blood Blood, serum Trace levels F Trace levels A B Iood , hair ng/g levels A A Serum, plasma - Hair Up to 300 pg/g A Human liver tissue Trace levels A Hair Trace levels A L L - L L L L L L L L L PTFE bomb at 120 "C.Cool, dilute and measure Ca, Cu, Fe. Mg, Zn by AAS and K, Na by FES, using pulse-nebulization technique Applications of mu It i-e lement AAS instrument, using continuum source and echelle monochromator. Examples : Cr in urine; Cu, Pb, Zn in blood, urine, serum; up to 8 elements in foods and biological reference samples Elements quoted : Cu, Fe, Zn, Mg, Ca F - Graphite furnace - - - Method for Cu, Zn, Cd, Hg, Pb, Mn in F - bovine blood and NBS-SRM No. 1571 Inter-laboratory comparison, using NAA F - and AAS methods Continuum source method F - Review (129 refs.) F - Graphite furnace Treat with HNO, in polyethylene vessels, Graphite furnace at 80 "C. Ash solution on filament before (CRA-63) analysis Sludy of inter-sample furnace cleaning Graphite furnace procedures Hair as biopsy material.(Elements : Graphite furnace Pb, Mn, Cd, Hg, Fe, Ni, Cu, Mg, Zn) Dry and ash i n low-temperature plasma F Air/C,H, asher. Extract with H,SO,/HNO,. (Elements : Mg, Ca, Mn, Fe, Cu, Zn, Rb, Rinse with ether/methanol, wash, dry, cut into 1 cm lengths and digest with HNO, + H,O, (Elements : As, Cd. Cu, Pb, Mn, Zn) Cd 1 Graphite furnace (HGA-2000) 160 163 241 373 407 408 41 3 414 463 k 2 b 487 s 493 3 5.% G 2 479 2, r, t! 518 $Various (7) Various Various Various Various (11) (7) Various Various Various Various Various Various Various Various Various Biological samples Trace levels Cattle tissue Blood Lung tissue Shells Marine organ i sm s Biological materials Biological materials Urine Biological samples Biological samples Biological samples Biological fluids Plasma fractions Trace levels Trace levels Trace levels (as fly ash) 0.4-3700 pg/g (various elements) Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels Trace levels Na6H;pellet hydride-evolution method F Air/C,H, 529 ,b W Chelation-precipitation technique, with Graphite furnace filtration through porous graphite crucible for direct introduction to furnace Centrifuge to separate plasma P ICP Method for estimation of fly ash in lung F - tissue by determination of AI, Si, Mg, Na, Li, K and Sc as monitoring elements Dissolve i n HCI, HNO, or HCIO, P ICP Digest with HNO, i n PTFE vessel.F Air/C,H, Results given for Cd, Pb, Cu, Mn, Zn, Cr Graphite furnace and Hg Cold vapour (Hg) Review F - Graphite furnace Review F - - P ICP - P ICP Review of experimental parameters P ICP Graphite furnace Application of Faraday effect to ETA-AAS system Blood-Haemolyse and dilute (1 : 4) F Air/C,H, with 0-02M HCI containing 0.5% Triton-X Urine - Nebulize directly Study of blood transport of essential F Air/C,H, and toxic metals by AAS coupled with biochemical separations, e.g., selective precipitation, ultrafiltration and gel chromatography Graphite furnace Trial of commercial tissue solubilizer (tetra-alkyl-NH,OH in toluene) i n comparison with conventional wet HNOJHCIO, digestion.Results given for AI, Cd, Cu, Mn Graphite furnace Various - Biological materials Trace levels A A E A E A A, F A E E E A F A A G 1, s L L L L, G L L L L L L L L L v for As; Sb, Bi, Ge, Te, Se, Sn + heated Sid, tube ", -. 553 r 2 2. z 563 586 643 658 6 72 675 705 739 878 912 936 968 970 ETable 4.9 . BODY TISSUES AND FLUIDS- continued 3 0 Element h/nm Matrix Concentration Tech. Sample treatment Atomization Ref. Form Various (8) Various Various Various (5) Various Various (5) Various (6) Various Various (5) Various (6) Biological fluids Trace levels A Biological samples Shark tissue Whole blood Serum Urine Cataractous lens tissue Animal tissues Breast tissue Sca ip hair Blood A - A A, E A - - A - Trace levels A Trace levels A Trace levels A Trace levels E L L - L L L L L L L L Review of analytical methods for Na.K, F Air/C,H, Ca, Mg, Zn, Cu, Fe, Mn i n serum, urine, faeces and intravenous fluids, with particular reference to Cu and Mn in urine Description of modifications t o carbon- rod furnace, to give better sample handling and improved sensitivity Preparation of shark powder and shark - - paste as biological standards Digest with HNOJHCIO,, evaporate to F - fumes, extract Fe(l1l) with HCI/MIBK, re-heat aqueous phase to fumes and adjust to pH 4 with NH,OH.Buffer with NH, acetate/acetic acid and extract metals (Co, Cu, Pb, Ni, Zn) with DDC/CHCI,.Back-extract into H,O Micro-injection technique (5-20 for F - Li, Na, K, Mg, Ca Application of Zeeman-effect background F - correction Method for Fe, Mg, Cu, Ag, Cd, Pb F - Graphite furnace Graphite furnace Nutritional study. Elements sought F - include : Ni, Cu, Fe, V, Cr, As, Zn Comparison of normal and diseased F - tissue, for Ca, Mg, Zn (FAAS) and Rinse in ether/methanol, wash, dry and HNO, + few drops H,O,. Calibrate by standard addition method. Elements : As, Cd, Cu, Pb, Mn, Zn - P ICP Graphite furnace Graphite furnace Graphite furnace Cd, CU (ETA-AAS) cut into 1 crn lengths. Digest with (HGA-2000) 996 1 000 1117 1188 1244 1245 1246 $ 5. 1302 1303 9 Y 1304 2. r/: '", 2 0 1305 $ 5 '4Various (5) Various Various ( 6 ) Blood Trace levels A Clinical samples Trace levels A Fish tissue Trace levels A Various (6) Various Various (14) Various ( 8 ) Various Various Various (9) Various (5) Various Various ( 6 ) Various Various ( 6 ) Hair Trace levels Biological samples Urine - Trace levels Whole blood Trace levels A Clinical samples Trace levels A Biological material I A Biological material Trace levels E E Human tissue - Biological samples - Bovine liver A Biological materials d Biological materials - L S L L L L L S S S L L L L Investigation of sample storage effects on determination of Cu, Zn. Pb, Cd and HgCold vapour (Hg) Review of applications and methods in a general hospital laboratory Comparison of 2 ETA-AAS techniques (a) direct furnace atomization and (b) atomization from graphite platform within furnace. For Cd, add (NH,),SO, solution before ashing. Elemenls : Cd, Zn, Pb, Co, Fe, Cu Wash and digest with acid in pressure F - vessel. Elements : Ca, Cu, Pb, Mg, Ni, Zn Zeeman-effect background correction Graphite furnace Pass 250 ml sample through column of P ICP poly(dithiocarbamate) resin. Wash with H,O and digest resin with HN03/H2S0, Comparison of 3 methods (ETA-AAS, F - Zeeman effect AAS, and NAA) Elements : Cd, Co, Cr, Cu, Mg, Mn, Pb, Zn 1 Applications review Graphite furnace Graphite furnace ( + graphite cup) Graphite furnace Graphite furnace Graphite furnace ( 1 : 1) Graphite furnace - Ash and mix with graphite powder. A D.c. arc (Study of matrix interferences) Elements : Ti, Cr, Co, Ni, Mo, Cd, Pb, V, Zn Place tissue slice (50 pm thickness) on Laser microprobe developed photographic plate and use Ag (LMA-1) from emulsion as internal standard for Al. Zn, Ca, Cu, Fe Review (14 refs.) Digest with HNO,/HCIO, i n PTFE bomb. F - Pulse-nebulization method (100 ELI) None Graphite furnace Description of ”absolute” analysis method Graphite furnace - - 1314 .5” 5, P 1315 1344 2; -. 1367 1528 1546 1579 1600 457 1822 1 e24 1896 1942 1955 1995 ,J

ISSN:0306-1353    

DOI:10.1039/AA9790900198

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

Analytical Atontic Spectroscopy NEW BOOKS Handbook of Decomposition Methods in Analytical Chemistry. R. Boek, translated by I. Marr, published by International Textbook Co., Glasgow, Scotland, 1979. (1 56) 1978 Annual Book of ASTM Standards. Pt. 42: Emission, Molecular and Mass Spectre copy, Chromatography, Resinography, Microscopy. American Society for Testing and Materials, Philadelphia, PA, U.S.A.(386) Spcctrochemical Analysis by Atomic Absorption, W. J. Price, published by Heyden, London, 1979. (415) Atomic Absorption Spectroscopy. M. Slavin, published by John Wiley & Sons, New York, U.S.A., 1978. (451) Handbook of Analytical Control of Iron and Steel Production. T. S. Harrison, published by Ellis Horwood, Chichester, distributed by Wiley, 1979. (503) Wilson & Wilson’s Comprehensive Analytical Chemistry, Vol. 9. R. Browning, S. Hofmann and P. Tschoepel, edited by G. Svehla, published by Elsevier, Amsterdam, 1979. (656) Modern Methods for Trace Element Analysis. M. Pinta, published by Ann Arbor Science Publishers Inc., Michigan, 1978. (667) The Analysis of Water; Natural Waters, Waste Water, Sea Water, 6th Edition. J. Rodier, C. Geoffray, G.Kovacsik, J. Laporte, M. Plissier, J. Scheidhauer, J. Verneaux and J. Vial, published by Dunod, Paris, distributed by Bailey Bros. and Swinfen. 1978. (1073) Analytical Laser Spectroscopy. Edited by N. Omenetto, published by John Wiley and Sons, New York, 1979. (1 138) Physical Methods in Modern Chemical Analysis. T. Kuwana, published by Academic Press, New York, 1978. (1139) Fundamentals of Analytical Flame Spectroscopy.C. T. J. Alkemade and R. Herrmann, published by Adam Hilger, Bristol, 1979. (1208) Mercury in Waters, Effluents and Sludges by Flameless Atomic Absorption Spectrophoto- metry. T. A. Dick, published by H.M.S.O., London, 1978. (1224) Calcium in Waters and Sewage Effluents by Atomic Absorption Spectrophotometry. Dept. of the Environment /National Water Council, published by H.M.S.O., London, 1978. (1 426) Flames. Their Structure, Radiation and Temperature. A. G. Gaydon and H. G . Wolfhard, published by Chapman and Hall, Andover, 1979. (1427) New Trends in Analytical Atomic Spectrometry, edited by “Ossolineum”. Contributors: 5. Czakow, J. Fijalkowski, B. Kucharzewski, B. Strzyzewska and J. Lipinski, Wroclaw, 1979. (1830)

ISSN:0306-1353    

DOI:10.1039/AA9790900222

出版商:RSC    

年代:1979

数据来源: RSC

摘要:

22 3 REVIEWS Air and water analysis by ICP Atomic absorption analysis biological blood coal environment iron and steel pharmacology trace metals applications, As, Sb, Se background correction light sources liquid chromatography ICP laser spark monochromatic radiation time resolved Atomic emission, flame Atomic fluorescence analysis Atomic spectroscopy, present tendencies Body fluids, Na, K Detcrmination of As, Sb, Se by AAS metals in pharmaceuticals Na, K in body fluids toxic metals trace elements in coal Laser excited luminescence Liquid chromatography/AAS Rare-earth elements, separation and determination Resonance scattering Trace elements, AAS determination by resonance scattering in biological mat eria 1 in iron and steel 1795 351, 1902 1518 675, 1896 414 1906 333 37 1 1226, 1925 415, 1247 453 423 1769 350, 366, 1911 1252, 1459, 1795, 1911 424, 1914, 1958 1210 452, 1902 342 1914 21 1918 1818 1925 1918 1252 415, 1247 1906 424 1769 1603, 349 415 1719 349 675 37 1

ISSN:0306-1353    

DOI:10.1039/AA9790900223

出版商:RSC    

年代:1979

数据来源: RSC