摘要:

AbstractIonic mass transfer coefficients between the wall and a liquid fluidized bed of 0.043 inch lead glass spheres have been measured using the diffusion controlled reduction of ferricyanide ion at a nickel cathode.The coefficients obtained are correlated in terms of the dimensionlessjfactor and are compared with dissolution mass transfer results by this author and with a recent liquid fluidized bed heat transfer study(1)with these same particles. It is concluded that in the dissolution study either mechanical erosion or roughness effects or both were present. No analogy was found to exist between overall heat and mass transfer in a liquid fluidized bed in which there is a large difference between the Schmidt and Prandtl numbers because the dominant resistance is different for the two cases.

ISSN:0008-4034    

DOI:10.1002/cjce.5450450601

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractAn experimental study concerning the plate efficiency is performed in bubbling regime and in foam regime, by means of a single tray column. Two mixtures have been used. One of them, the system cyclohexane‐toluene was selected since its surface tension is practically independent of concentration, while the other system (methanol‐water) was selected because its surface tension depends strongly on concentration.For the bubbling regime, experiments lead to the conclusion that the plate efficiency depends in the same manner for both mixtures on composition (the curves of efficiency vs. composition present a weak maximum) though the Marangoni effect does not occur for the first system and has favorable conditions of occurrence for the second system.For the foam regime the efficiency is practically equal to unity for all compositions.In the theoretical part of the paper several possible mechanisms of the rectification process are discussed. One is based on the diffusional model derived from the classical theory. Three other equations are based on the assumption that vaporization in the bulk of the liquid occurs too. A criterion for the occurrence of this thermal effect is given.A possible explanation of the non‐occurrence of the thermal effect in cases for which the above mentioned criterion leads to a contrary conclusion, is also inc

ISSN:0008-4034    

DOI:10.1002/cjce.5450450602

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA sufficient condition under which a tubular reactor with axial diffusion is globally stable is derived by use of the maximum principle for parabolic equations. It is shown that by use of some topological concepts the asymptotic stability of a steady state can be determined without the necessity of performing any computations. If a unique steady state exists it is asymptotically stable. If three steady states exist, the high and low temperature steady states are asymptotically stable, while the intermediate one is unstable.

ISSN:0008-4034    

DOI:10.1002/cjce.5450450603

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe Two‐Derivative Method of optimization, recently described by Methot, Cloutier and Cholette, has been shown to be a special case of the Newton‐Raphson Method, and results when the matrix of second derivatives is assumed to be diagonal. Examples are given to illustrate that the Two‐Derivative Method may diverge if a convergence forcer is not used. A simple form of forcer is shown to improve convergence, and it is suggested that a forcer should always be used with this m

ISSN:0008-4034    

DOI:10.1002/cjce.5450450604

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe kinetics of the reaction\documentclass{article}\pagestyle{empty}\begin{document} 2{\rm H}^ + + {\rm ClO}_2 ^ - + {\rm Cl}^ - \rightarrow {\rm ClO}_2 + 1/2{\rm Cl}_2 + {\rm H}_2 {\rm O} \end{document}have been studied at 25°C. in strong acid solution; the effects of acidity, chloride, chlorate and chlorine are reported.A mechanism is postulated to interpret the peculiar features of this reaction as well as the stoichiometry and some of the kinetics of the parallel reaction\documentclass{article}\pagestyle{empty}\begin{document} 6{\rm H}^ + + {\rm ClO}_2 ^ - + 5{\rm Cl}^ - \rightarrow 3{\rm Cl}_2 + 3{\rm H}_2 {\rm O} \end{document}The mechanism involvesHClO2andHOClas intermediates\documentclass{article}\pagestyle{empty}\begin{document} 3{\rm H}^ + + 2{\rm Cl}^ - + {\rm ClO}_3 ^ - \rightleftharpoons {\rm Cl}_2 + {\rm HClO}_2 + {\rm H}_2 {\rm O}.....{\rm (a)} \end{document}\documentclass{article}\pagestyle{empty}\begin{document} {\rm HClO}_2 + {\rm H}^ + + {\rm ClO}_3 ^ - \rightarrow 2{\rm ClO}_2 + {\rm H}_2 {\rm O}.....{\rm (b)} \end{document}\documentclass{article}\pagestyle{empty}\begin{document} {\rm HClO}_2 + {\rm H}^ + + {\rm Cl}^ - _. \rightarrow 2{\rm HOCl}.....{\rm (c)} \end{document}\documentclass{article}\pagestyle{empty}\begin{document} {\rm HOCl} + {\rm H}^ + + {\rm Cl}^ - \rightarrow {\rm Cl}_2 + {\rm H}_2 {\rm O}.....{\rm (d)} \end{document}General rate expressions are derived for the formation of chlorine dioxide and chlorine, and the individual rate constants are calculated. An expression is obtained for the relationship between the ratio of chlorine dioxide to chlorine produced and the ratio of chlorate to chloride

ISSN:0008-4034    

DOI:10.1002/cjce.5450450605

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractUsing generating functions, models for polymerization reactors are developed without using kinetic approximations. One of the models is then used for the optimization of a series of tank reactors in which free radical polymerization is taking place. It is found that peak‐seeking methods are a convenient and efficient method of optimizing such systems. Curves showing “optimal” design alternatives are generated for the simple example tr

ISSN:0008-4034    

DOI:10.1002/cjce.5450450606

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe pyrolysis of ethane and propane has been performed in the presence of carbon vapor at temperatures between 2,000°K and 5,000°K. This high energy environment is obtained by an electric arc struck between two graphite electrodes. The quenched gases are analyzed by gas chromatography.The major reaction products are acetylene and hydrogen. C2H2yields are a function of the C/H2, ratio, the power input, the reaction temperature and the total pressure.Power levels between 10 and 50 kw. and gas flow rates of 1.5 to 20 liters per minute have been used. The electric arc process of hydrocarbon cracking is compared with conventional methods of acetylene productio

ISSN:0008-4034    

DOI:10.1002/cjce.5450450607

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA kinetic investigation on the oxidation of methane using a palladium catalyst was conducted. Conversions of methane were small and limited to about 10% to facilitate the use of initial rate approach. Plots of initial rate against total pressure and varying feed composition were used to interpret the data qualitatively. Regression coefficients from linearized rate equations and criteria of best fit were used to arrive at a plausible mechanism. The experimental results indicated that the reaction rate is controlled by surface reaction in which the adsorbed oxygen and adsorbed methane react to produce adsorbed carbon dioxide and adsorbed water.

ISSN:0008-4034    

DOI:10.1002/cjce.5450450608

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractMethods of predicting gas‐liquid diffusion coefficients are reviewed. A study has been made on the diffusion of carbon dioxide into a range of organic liquids and hydrocarbon mixtures over a sixty fold range of solvent viscosity. All available models for predicting diffusion coefficients were tested. It is shown that the data presented are best fitted by Arnold's equation.Until more exact models to represent the liquid state are available this affords a reliable method for correlating gas‐liquid diffusion d

ISSN:0008-4034    

DOI:10.1002/cjce.5450450609

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA predictive theory based on the modified absolute rate theory is extended to the prediction of diffusion coefficients in the concentrated regions of multicomponent liquid systems without the use of adjustable parameters. A scheme for the direct prediction of multicomponent diffusion coefficients in non‐associated liquid systems is presented, analysed and tested with available dat

ISSN:0008-4034    

DOI:10.1002/cjce.5450450610

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY