Abstract :
In a recent paper (J. A. Dumesic, J. Catal.185, 496 (1999)), Dumesic argued that “DeDonder relations offer a rigorous approach for assessing whether a reaction scheme contains a rate determining step.” Here, we argue that, while analysis with DeDonder relations is a very powerful approach that has many advantages, it has a limitation with respect to finding the rate determining step, and another method, previously proposed by this author (C. T. Campbell, Topics Catal.1, 353 (1994)) involving the “degree of rate control,” is preferable in that particular respect. An approach for extending this latter method to transient kinetic conditions is also suggested.