Consequence of Temkins theory and search for best catalysts

5 Consequence of Temkin s theory and search for best catalysts 

A concept of distribution function 7 of active sites was introduced in the deduction of Temkin theory, from which well-known expressions for adsorption isotherms, such as Freundlich s and Prumkin-Temkin s isotherms and others, and for rate laws of adsorption such as Elovich s one were obtained. Analjdical forms of isotherms depend on the forms of adsorptive energy distribution function, because the physical meaning of these distribution function is based on the inherent non-uniform of catalyst surfaces and the interaction between adsorbed species. Therefore, this formulation accounts for two physical effects caused by non-ideality of adsorptive phase. 

It can be seen from the above-mentioned discussion that the Temkin s theory of catalytic reaction kinetics on heterogeneous surfaces is confirmed not only by overall reaction kinetic data of ammonia synthesis, isotherms and adsorptive rates of nitrogen on iron catalysts, more importantly, perhaps, but also some very useful generalization results derived from this theory. For instance, Temkin s equation is obtained based on two steps or simplified two steps mechanism. So, it can apply to any kind of catalytic reactions. The problem is Are some simplifications required by reasonable formation of two step mechanism, and can the assumption of rate determining step be made for non-uniform surface The answer of Temkin s theory is positive, and especially Temkin s theory of catalytic reaction kinetics on non-uniform plays an important role in solving the selection and improvement of catalysts. 

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