Strategien kinetischer Experimente mit desaktivierenden Katalysatoren

Strategies of kinetic experiments with decaying catalysts . Rate expressions for solid‐catalyzed gas‐phase reactions may be misleading, useless, or at least incomplete, unless they cover the changing catalyst activity and selectivity. To prepare the ground for complete kinetic modelling of such systems, concentration‐controlled rate measurements in gradient‐free reactors appear the most appropriate method. They allow uncoupling of concentration and activity effects upon the rates. Based on this possibility, strategies have been developed for testing the rate laws, prior to modelling them, for separability into reaction and deactivation terms. Not only in connection with such strategies, but also apart from any catalyst decay, concentration control allows decomposing reaction networks into smaller and more amenable subsets by adjustment of partial equilibrium, as well as carrying out rate measurements at selected concentrations, i. e. according to experimental designs.