Analysis and correlation of rate data

The mathematical models generally used for correlation of rate data on soUd-catalyzed reactions fall into two broad classifications  

Considering that chemisorption is a chemical reaction restricted to the surface layer of the catalyst, the dependence of adsorption equilibrium coefficients, Kj, is also expressed in terms of the van t Hoff equation, with AH js being used instead of AH  

In heterogeneous kinetics, the experimentally observed rate constant is an apparent rate constant, k pp, and the activation energy obtained from it is also apparent activation energy, E pp, which is a relatively complex combination of Etrue with AHads of reactants and products. It is difficult to identify the separate components of Eapp unless a specific experimental design is formulated. 

In part (d) of Example 1, the experimentally observed apparent rate constant, kf, is equal to ksrKAKp). Therefore, 

Since chemisorption is mostly exothermic, the heats of adsorption for reactants A and B are negative, and the measured Eapp is lower than Etrue by the sum of AHa + AHb - 

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