General Information and Fundamentals of the Process

Most synthetically useful catalytic processes are run over metal catalysts which, as outlined in Fig. 8.2, can be composed of a single metallic component or a mixture of metals. Either of these types can be supported or unsupported. Metal catalysts are used primarily for hydrogenations, hydrogenolyses, isomerizations and oxidative dehydrogenations. They are rather easily prepared in a pure form and can be characterized without too much difficulty. Because of this, metal catalysts are generally preferred for basic research. Such materials have been used to obtain almost all of the fundamental information on which the various theories of catalysis have been derived. A general discussion of catalytically active metals and the factors influencing their activity is presented in Chapter 11 while Chapter 12 deals with the preparation and properties of the various types of unsupported or bulk metal catalysts. The preparation and properties of the supported metal catalysts are presented in Chapter 13. 

Simulation is based on the fundamental physics of the process and therefore always has the potential of giving more realistic information on the performance of the process than that of methods based on dimensional analysis, mechanistic approximations, or space-averaged (one-point) theories or correlations, provided that the model equations are well defined. The directional changes shown by the simulations should in general be the same as the experimental ones, and the magnitudes of those changes should also be similar. 

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