Role of diffusion in pellets Catalyst effectiveness

Role of diffusion in pellets Catalyst effectiveness Catalysts are normally used in the form of pellets, except in fluidized bed reactors where powders are used. Thus, problems of resistance to diffusion within the pellets are common. These have been quite extensively studied and many 

The basic requirement in any study of internal diffusion is an understanding of the various modes of transport in a straight capillary bulk, Knudsen, configurational, and surface. This knowledge is then extended 

The resistance to diffusion (expressed in terms of an effective diffusion coefficient as defined above) has the effect of progressively reducing the concentration of the reactant molecnle from the catalyst snrface to the center. This leads to a lower reaction rate and to a lower valne of the 

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Chapter 7 Catalysis by Solids, 2 The Catalyst and Its Microenvironment, 171 Modeling of Solid Catalyzed Reactions, 171 Role of Diffusion in Pellets Catalyst Effectiveness, 183 Effect of External Mass and Heat Transfer, 201 Combined Effects of Internal and External Diffusion, 204 Relative Roles of Mass and Heat Transfer in Internal and External Diffusion, 205 Regimes of Control, 206... 

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