Redox Reactions The Mars-van Krevelen Rate Law

Oxidation reactions represent one family of reactions which may very well involve only irreversible steps, especially those reactions conducted at low temperatures. An early model to describe such reactions on an oxide catalyst 

Unfortunately, the derivation of this rate law is incorrect, and it is worthwhile to examine the proposed model to clarify why this is so. These two authors formulated their model using two irreversible steps written as  

A first-order dependence on R was assumed, and the rate, step 7.26, was stated to be  

For the second step, the rate of reoxidation (O2 adsorption) was assumed 

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