Chemical reaction with mass transfer

G. Astarita, Mass Transfer with Chemical Reaction, Elsevier, Amsterdam, 1966. 

G. Astarita, Mass Transfer With Chemical Reaction, Elsevier Publishing Co., Amsterdam, the Netherlands, 1967 C. Y. Wen and L. T. Pan, Models for... 

In order to establish the conditions for thermodynamic feasibility of reactive mass exchange, it is necessary to invoke the basic principles of mass transfer with chemical reactions. Consider a lean phase j that contains a set Bj = z —... 

Astarita, G., 1967. Mass Transfer With Chemical Reaction. Amsterdam Elsevier. 

Wachi, S. and Jones, A.G., 1991a. Mass transfer with chemical reaction and precipitation. Chemical Engineering Science, 46, 1027-1033. 

When the half-life time of reaction and the half-life time of micromixing in the absence of chemical reaction are of the same order or the former is less than the latter, the role of micromixing may become crucial. For instance, nitration or bromination of resorcinol, even when the ratio of moles of resorcinol to moles of bromine is high, can lead to predominantly disubstituted product contrary to the general belief. In such cases, in many respects, the theory of coupling between reaction and micromixing has parallels with the formalism of theory of mass transfer with chemical reaction (Bourne, 1983). 

Hofmann, H., 1983. in Mass Transfer with Chemical Reaction in Multiphase Systems, Vol. II Three-Phase Systems , Erdogan, A. (Ed.), Martinus Nijhoff Publishers, the Hague. 

Morsi, B. I., and Charpentier, J. C., On mass transfer with chemical reaction in multiphase systems. NATO ASI CESME, Izmir, Turkey, (1981). 

Note that Eq. (3) (respectively Eq. (2)) is in fact the definition of the liquid (gas) film thickness dL (dG), which cannot be measured because it does not really exist. The advantage of this model is its simplicity, its teaching power, and its ability to describe the coupling of mass transfer with chemical reactions sufficiently accurately for most practical cases. 

In this paper only isothermal simulations have been conducted to show the important features of the model to describe mass transfer with chemical reaction. In many industrial processes, distillation, reactive distillation and some absorption processes, heat effects play an important role and therefore cannot be neglected. These effects will be discussed in Part II. 

Astarita, G. Mass Transfer with Chemical Reaction, Elsevier, Amsterdam, 1967. Erank-Kamenetskii, D. A. Diffusion and Heat Transfer in Chemical Kinetics, Plenum Press, New York, 1969. 

The square of the uranyl nitrate concentration is required in the kinetic analysis. Mass transfer with chemical reaction (16, 83) is, however, too specialized a subject to be discussed fully here. 

In what follows, the preceding evaluation procedure is employed in a somewhat different mode, the main objective now being to obtain expressions for the heat or mass transfer coefficient in complex situations on the basis of information available for some simpler asymptotic cases. The order-of-magnitude procedure replaces the convective diffusion equation by an algebraic equation whose coefficients are determined from exact solutions available in simpler limiting cases [13,14]. Various cases involving free convection, forced convection, mixed convection, diffusion with reaction, convective diffusion with reaction, turbulent mass transfer with chemical reaction, and unsteady heat transfer are examined to demonstrate the usefulness of this simple approach. There are, of course, cases, such as the one treated earlier, in which the constants cannot be obtained because exact solutions are not available even for simpler limiting cases. In such cases, the procedure is still useful to correlate experimental data if the constants are determined on the basis of those data. 

Liquid Phase Mass Transfer with Chemical Reactions... 

Fig. 4.2. Liquid phase concentration profiles for mass transfer with chemical reaction - film theory...

In the last decade we have performed some thousands of experiments in packed adiabatic tubular reactors (CO oxidation), however, we have never observed oscillations. If on certain catalysts (e.g., Pt/Al203) the oscillation are caused by the kinetic mechanism then, apparently, the interactions of heat and mass transfer with chemical reaction suppress the occurence of periodic activity in tubular reactors. 

E will be different from 1 only if R4 is small relative to / 2, resulting in a bulk concentration of c — 0 and in a real parallel mechanism of the enhancement. The advantage of the concept of the enhancement factor as defined by eq 33 is the separation of the influence of hydrodynamic effects on gas-liquid mass transfer (incorporated in Al) and of the effects induced by the presence of a solid surface (incorporated in E ), indeed in a similar way as is common in mass transfer with homogeneous reactions. The above analysis shows that an adequate description of mass transfer with chemical reaction in slurry reactors needs reliable data on ... 

Astarita, G. "Mass Transfer with Chemical Reaction" ... 

Goelller, L. A., and R. L. Pigford, in Proceedings of the Symposium on Mass Transfer with Chemical Reaction (J. M. Pirier. ed ). Institute of Chemical Engineers. London, 1968. 

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