摘要:

AbstractThe conditions for concentrating the fluorozirconate ion by ion flotation with aminium salts as collector were studied. The effect of changed bubble rate, concentration of collector and zirconiumfluoride ratios as well as change of pHwere examined and collection into a solvent was also studied. Maximum recovery was 80%.

ISSN:0021-8871    

DOI:10.1002/jctb.5010150301

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractThe atmospheric oxidation of ethyl linoleate on a cotton substrate has been studied at 22 and 50°. The concentrations of conjugated diene hydroperoxide, conjugated triene diene ketone, and the development of a yellow coloration were obtained as functions of time by reflectance spectrophotometry at 234, 268/275 and 350 mμ respectively. Both the primary and secondary stages of the oxidation were affected by pretreating the cotton with sodium carboxymethyl cellulose and sodium ethylenediaminetetra‐acetate. A qualitative similarity exists between the extinction coefficients obtained from this investigation and those calculated from a bulk‐phase oxidation, but reflectance measurements at 234 mμ indicate that the conjugated hydroperoxide formed in the initial stages of the oxidation is considerably less stable on the cotton substrate than in the bulk‐est

ISSN:0021-8871    

DOI:10.1002/jctb.5010150302

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractA study has been made of the thermal hydrocracking ofo‐,m‐ andp‐cresol in the temperature range 580—700° at pressures up to 390 p.s.i.g. with hydrogen/cresol ratios ranging from 0.8/1.0to 4.0/1.0 in a continuous flow reactor. The main products of the reaction, analysed by gas chromatography, are toluene and phenol (primary products) and benzene (secondary product). Small amounts of 2,6‐xylenol are present in the products fromo‐cresol.In the presence of excess hydrogen the results for the overall rate of hydrocracking are found to fit a 1.5‐order rate equation, first‐order with respect to the cresol and 0.5‐order with respect to hydrogen. A possible mechanism for the main reactions taking place has been suggested which accords with the rate equations obtained experimentally.As the hydrogen/feed ratio is reduced below 1.0/1.0 the products become more complex and the 1.5‐order rate equation no longer applies. When nitrogen is used instead of hydrogen, i.e., under conditions of thermal cracking, the results are found to fit a first‐order rate equation which agrees with that proposed by Neuworth&Jones.The rate constants for the hydrocracking of the cresol isomers are found to be in the

ISSN:0021-8871    

DOI:10.1002/jctb.5010150303

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractThe oxidation of three types of uranium dioxide (UO2) material has been investigated in the 120—360° range.In UO2powders, of surface area greater than about 2 m.2/g., oxidation was diffusion‐controlled up to U3O7which oxidised to U3O8above about 240°. The activation energies were in the range 20—27 kcal./mole.For material with very low surface‐area, both electrolytic UO2powder (0.0405 m.2/g.) and sintered pellets (5 cm.2g.) were oxidised by nucleation and growth controlled processes. The growth activation energies for the two materials were 32.19 and 26.38 kcal./mole respectively. Considerable differences occurred in the oxidation rate of pellets from batch to batch.Material with intermediate surface‐area comprising sintered powder (0.135 m.2/g.) and crushed sintered pellets (0.095 m.2/g.) gave oxidation curves which were hybrid between the other two types above. At a high enough temperature (∼ 420°), the 0.095 m.2/g. material showed a completely sigmoid ‘nucleation’ type of curve.X‐Ray diffraction studies were performed at intermediary stages in the oxidations to trace the presence of the γ‐UO2phase, and suggestions are put forward to explain the above d

ISSN:0021-8871    

DOI:10.1002/jctb.5010150304

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractVapour‐liquid equilibrium data were determined at atmospheric pressure for the system ethanolbenzene‐cyclohexane using a modified Gillespie still. The thermodynamic consistency of the data was tested by the Li&Lu met

ISSN:0021-8871    

DOI:10.1002/jctb.5010150305

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractA comparison of micropore size distributions in the range below 100 Å has been made for a silica gel sample, using the results of exact and approximate Barrett, Joyner&Halenda computations and of the recently proposed method of Dollimore&Heal. A number of discrepancies were noted between the results of the computations; in particular, while total surface areas obtained from the determinations of Barrett, Joyner&Halenda were within 2% of the BET surface area, the value from the Dollimore&Heal computation was about 20% smaller.The various methods which have been proposed for pore size distribution are essentially the same in theory; discrepancies such as those noted in this work are attributed to the differing values of adsorbed multilayer thickness used in the calculations. Although there is little agreement among the published correlations of multilayer thickness for nitrogen adsorption, the Halsey eqauation which is employed by Dollimore&Heal, lies well above other correlations and must be regarded as of questionable value in distribution computations. A satisfactory multilayer thickness correlation should provide a means of accounting for the effects of pore structure and non‐ideal adsorption; the approach suggested by Mingle&Smith may be promising in this directi

ISSN:0021-8871    

DOI:10.1002/jctb.5010150306

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractSingle spheres ofo‐,m‐ andp‐hydroxybenzoic acid have been dissolved into a water stream (Rerange 100—1000) and the data are correlated by a relationship of the formThemeta‐isomer (ϕ = 0.80) behaves differently from theortho‐ andpara‐isomers (ϕ = 0.71) and it is suggested that this is due to the influence of surface effects on the dissolution process. A quantity termed the ‘work of replacement’, which can be calculated from surface tensions and wetting angles, has been defined to give a measure of the influence of these effects.Solubility, density, viscosity and diffusivity data are presented for saturated aqueous solutions of the three hydroxybenzoic acids. Differences in diffusivity of the isomers are explained by considering the effects of dimerisation due

ISSN:0021-8871    

DOI:10.1002/jctb.5010150307

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractA three‐constant conic equation is proposed for correlating and testing the consistency of nonideal and near‐ideal binary vapour/liquid equilibrium data.The conic equation is based on the geometry of excess thermodynamic functions and the constants are simply related to the partial molal excess functions at infinite dilution and to the maximum value of the excess funct

ISSN:0021-8871    

DOI:10.1002/jctb.5010150308

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010150309

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY