Microkinetic analysis defined

More recently a hybrid approach to computer-assisted catalyst synthesis, based on a microkinetic analysis of the catalytic reaction, has been put forward which comprises essentially deterministic but also some non-deterministic features. For the synthesis of a catalyst with high activity and selectivity for a given reaction, the application of a microkinetic analysis has been suggested by Dumesic and co-workers [43-45]. The derivation of the microkinetics is not necessarily based on detailed kinetic experimentation but, by analogy, to similarities with other known catalytic processes. In an ideal situation, the microkinetics of a catalytic reaction are completely defined according to Dumesic and his collaborators when ... 

Microkinetics as defined by Dumesic, is the examination of catalytic reactions in terms of elementary chemical reactions that occur on the catalytic surface and their relation with each other and with the surface during a catalytic cycle. This definition can easily be expanded into covering non-catalytic systems as well. Microkinetics, for the most part, has focused on analysis or understanding of the reaction mechanism. The approach, however, also holds the promise of being used to aid in the synthesis of new materials. Microkinetic modeling is now an important tool for many of the practicing reaction engineers. This approach enables one to formulate and follow the detailed concentration profile for most if not all of the reaction intermediates. 

The models developed here account for unmeasurable intermediates such as adsorbed ions or free radicals. Microkinetic analysis, pioneered by Dumesic and cowokers"", is an example of this approach. It quantifies catalytic reactions in terms of the kinetics of elementary surface reactions. This is done by estimating the gas-phase rate constants from transition state theory and adjusting these constants for surface reactions. For instance, isobutane cracking over zeolite Y-based FCC catalysts has 21 reversible steps defined by 60 kinetic parameters." The rate constants are estimated from transition state theory... 

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