摘要:

AbstractA semiempirical expression for the Helmholtz energy of mixed electrolyte solutions in solvents mixtures is obtained from the solution of the mean spherical approximation given by Planche and Renon (1981) for a nonprimitive model of interactions. A consistent set of analytical equations for the related thermodynamic properties was further derived and used to represent osmotic coefficient data of strong aqueous electrolytes at 25°C. Data correlation was performed on more than 80 systems up to a 6 M molality using generally one adjustable parameter for each single electrolyte; from these parameters the properties of mixtures can be calculated in a predictive manner without additional parameters

ISSN:0001-1541    

DOI:10.1002/aic.690310802

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe theory of deposition of compressible, particulate beds on cyclindrical surfaces is developed for both constant‐pressure and constant‐rate filtration. Radial flow is encountered in tubular filters and in both filtering and sedimenting centrifuges. It differs mathematically from filtration on planar surfaces in the manner in which the frictional drag balance on the particle structure is coupled with Darcy's equat

ISSN:0001-1541    

DOI:10.1002/aic.690310803

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe combustion of processed shale is analyzed. By using a coordinate system moving with the same velocity as the combustion zone a model is obtained for the fully developed temperature wave. Of particular interest is the interpretation of this wave in terms of the kinetics and thermal effects of the reactions that are involved.

ISSN:0001-1541    

DOI:10.1002/aic.690310804

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe combustion retorting of oil shale is analyzed. By using coordinate systems moving at the same velocity as reaction zones, a model is obtained for the fully developed thermal wave which would exist after the wave has progressed a sufficient distance into the bed. Of particular interest is the interpretation of oil yield in terms of the structure of the wave and of operating variables.

ISSN:0001-1541    

DOI:10.1002/aic.690310805

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractA mathematical model of the hydrodynamic processes occurring in a periodic cycled plate column is developed and experimentally confirmed. The model is applied to the prediction of the holdup distribution and the investigation of hydrodynamic problems. An effective manifold arrangement is proposed to minimize the uneven liquid draining encountered in previous experimental studies.

ISSN:0001-1541    

DOI:10.1002/aic.690310806

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractTheoretical and experimental studies have been conducted on the mass transfer rates which occur during the continuous devolatilization of bubble‐free polymeric solutions in a corotating twin‐screw extruder. Experimental measurements of the mass transfer rates, when reported in terms of the product of the individual liquid phase mass transfer coefficient and the surface area for mass transfer per unit volume of empty extruder, were found to correlate well with screw speed in accordance with the predictions of a model based on penetration theory. It is shown, however, that significant differences exist between the measured and predicted values for the rates of mass transfer, which leads to the conclusion that the surface area for mass transfer is substantially smaller than the value computed on the basis that continuous films are formed on the surfaces of the screws and the barrel w

ISSN:0001-1541    

DOI:10.1002/aic.690310807

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe kinetics of the reaction of carbon dioxide with mono‐ and diethanolamine in such nonaqueous solvents as methanol, ethanol, and 2‐propanol and in water were studied using a stirred tank absorber with a plane gas‐liquid interface at 303 K. The reaction was found to be of first order with respect to carbon dioxide for every solvent. The order of reaction with respect to ethanolamine was found to be unity only for an aqueous solution of monoethanolamine and for the other solutions, ranged from 1.4 to 2, depending on the solvent species. The reaction order was increased in the order of water, methanol, ethanol, and 2‐propanol. The variation of the reaction order with the solvent species could be explained in terms of a reaction scheme via a zwitterion. Almost linear dependence of the logarithm of the reaction rate constant on the solubility parameter of the solvent was

ISSN:0001-1541    

DOI:10.1002/aic.690310808

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe temperature rise at a gas‐liquid interface due to heat evolution and the relevant enhancement factor for gas absorption rate are analyzed for absorption, with an instantaneous irreversible reaction and with a first‐order irreversible reaction allowing for the temperature dependence of the major physicochemical properties. The analysis reveals that, unlike isothermal absorption, the film theory solutions with the replacement of any system parameters do not give a reasonable approximation to the realistic penetration theory solution, except in the case of the physical absorption regime. However, the modified Danckwerts analysis, in which the physicochemical properties are evaluated at the time‐averaged interface temperature, is shown to be useful in obtaining the approximate penetration theory solutions with satisfactory acc

ISSN:0001-1541    

DOI:10.1002/aic.690310809

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe etch‐decoration transmission electron microscopy technique was used to measure the turnover frequencies of the C‐CO2reaction in the temperature range 600–900°C. The absolute rate constants of the elementary rate steps were determined, and were in reasonably good agreement with statistical theories. The rates on monolayer steps of graphite were higher than those on multilayer steps by approximately four orders of magnitude at 800°C, because the CO bond in the reaction intermediate is stronger by about 9 kcal/mol on the monolayer steps. The rates of vacancy formation in the lattice were also determined. The vacancies are formed by atomic oxygen dissociated

ISSN:0001-1541    

DOI:10.1002/aic.690310810

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractActivated carbon beds with adsorbedn‐octane are regenerated using hot air. Effects of pressure, feed temperature, and initial loading on temperature and concentration breakthrough curves are studied. For moderate and high values of these variables, effluent vapors are found to be saturated with hydrocarbon during part of the heating step, indicating the presence presence of liquid within the bed. Regeneration behavior is predicted with reasonable accuracy using a nonisothermal stage mode

ISSN:0001-1541    

DOI:10.1002/aic.690310811

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY