摘要:

A procedure using a flow dynamic chemisorption technique is developed in this paper to determine the internal metal surface area distribution within a metal supported catalyst and dynamic parameters—the effective diffusivity and the rate constant for chemisorption.

ISSN:0098-6445    

DOI:10.1080/00986448608911774

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The nonideal concentration dependent sorption selectivity for the liquid-solid interface was analyzed by introducing the admolecular interaction in the statistical thermodynamic approach. The quasi-chemical and Bragg-Williams approximations together with the maximum term condition result in the desired expression for the adsorption isotherm. Experiments were carried out for the adsorption of the binary (xylene/toluene) mixture on the Y-zeolite as a nonideal system. The derived isotherms were correlated with both the ideal system reported by Sircar and Myers and the present nonideal adsorption data.

ISSN:0098-6445    

DOI:10.1080/00986448608911775

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A linear stability theory is developed to examine the stability of a radially bounded foam or emulsion film with tangentially immobile interfaces. The results indicate that the drainage flow has a very significant effect on the marginally stable film thicknesses. The predicted values of critical thickness are in good agreement with those measured with the interference microscopic technique for both foam and emulsion films.

ISSN:0098-6445    

DOI:10.1080/00986448608911776

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Die-swell and torsional balance experiments were performed to measure the shear and normal stresses developed by AMK (0.3% FM-9 + glycol/amine in Jet A) and 0.1% ARCO in Jet A. Capillary tube experiments show that AMK shear thickens at a critical shear rate, reaches a maximum viscosity and then shear thins at higher shear rates. Despite the fact that the antimisting fuel made with the ARCO polymer exhibits a more conventional shear stress dependency (i.e., shear thinning), die-swell measurements indicate that both fuels develop large normal stresses at high shear rates. While the torsional balance method was able to obtain both shear and normal stress information for the ARCO polymer at high shear rates, AMK exhibited anomalous behavior that made it impractical to measure normal stresses by this method. A comparison of normal stresses for the ARCO polymer indicates that normal stresses measured by these two methods differ significantly in magnitude.

ISSN:0098-6445    

DOI:10.1080/00986448608911777

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Experiments are described in which an improved die-swell rheometer has been developed for real-time quality control of AMK. This improved apparatus includes the use of differential pressure taps that make it unnecessary to correct for end effects and an optical probe that measures the die-swell automatically. In the range of 0.25 to 0.35 wt% FM-9, changes in polymer concentration had a small but measurable effect on die-swell. However, normal stresses calculated from die-swell and expressed as a function of the wall shear rate showed no dependency on polymer concentration. Consequently, normal stresses calculated in this manner are of little use for quality control purposes. The reason for this failure is thought to be associated with several of the assumptions used in the analysis of die-swell in terms of normal stresses. Nevertheless, die-swell itself is a viscoelastic phenomenon that can be used for quality control of AMK. The sensitivity of die-swell to polymer concentration can be improved by conducting experiments at lower Reynolds numbers (i.e., by using smaller diameter tubes and working at shear rates closer to the maximum apparent viscosity).

ISSN:0098-6445    

DOI:10.1080/00986448608911778

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The breaking of seven ternary acetate-alcohol-water azeotropes by extractive distillation was accomplished. They aren-propyl acetate-n-propanol-water, isopropyl acetate-isopropanol-water,n-butyl acetate-n-butanol-water, 2-butyl acetate-2-butanol-water, isobutyl acetate-isobutanol-water,n-amyl acetate-n-amyl alcohol-water andn-hexyl acetate-n-hexanol-water. The acetates, usually the highest boiling constituents, are obtained as overhead product as a two-phase mixture with water. The most effective agents are glycols and dimethylsulfoxide. Solubility parameters were found to be a qualitative indication for selecting extractive distillation agents. When the formation of a chemical complex is dominant, solubility parameter does not explain solution behavior satisfactorily.

ISSN:0098-6445    

DOI:10.1080/00986448608911779

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The major mode of heat transfer in industrial combustion furnaces is that of radiation. The effects of radiative scattering are therefore of great importance in furnace design. This study investigates the behavior of both anisotropic and isotropic scattering using a computer-simulated model of a typical combustion furnace

ISSN:0098-6445    

DOI:10.1080/00986448608911780

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Expressions for limiting currents are obtained to describe the heterogeneous electroxidation of a suspended solid particle in a stirred electrolyte. The electrochemical reaction involves oxidation of a dissolved cation (mediator) in the electrolyte followed by oxidation of the solid coal particle by the cation via an irreversible pseudo first order chemical reaction. This model is applied to bulk electrolysis of the acidic coal slurries containing dissolved Fe(II), and the observed limiting currents permit evaluation of the chemical rate constant of coal oxidation. In addition to Fe(III), multivalent cation of Cu(II) was found to enhance the rates of electrochemical oxidation of coal.

ISSN:0098-6445    

DOI:10.1080/00986448608911781

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

This paper presents some new experimental data for axial solid distribution in batch slurry reactors. The effects of liquid and solid properties on the solid dispersion behavior in 0.076 m and 0.305 m diameter slurry bubble columns are outlined. The effects of gas distributor, column internals and particle size distribution on the solids concentation profiles are also examined. Critical gas velocity for complete suspension of solids are measured and compared with those predicted from the available literature correlations. It is shown that when the particles are completely suspended, the Peclet number obtained from the sedimentation-dispersion model depends very significantly on the assumed boundary conditions. The effect of gas velocity on the particle Peclet number depends on the nature of the liquid-solid system.

ISSN:0098-6445    

DOI:10.1080/00986448608911782

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The objective of this study was to consider the feasibility of using a predispersed solvent (decane) extraction/flotation process, involving a very low solvent/feed ratio, to remove dissolved hazardous organics, e.g. ortho dichlorobenzene from wastewaters. Procedures have been established for formulating and characterizing these predispersed solvents (polyaphrons) produced and for evaluating performance in extraction/flotation studies. Extraction/flotation using selected ca. 15 micron diameter polyaphrons in conventional mixer/separator with typical short hold-up times were 5 to 10 times more effective in removing ortho dichlorobenzene from water (less than 1/500 solvent to feed ratio) than with identical tests using a similar quantity of straight solvent. Initial results look encouraging, but further process evaluation of various applications will be required to assess the potential for this new separations process.

ISSN:0098-6445    

DOI:10.1080/00986448608911783

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor