Axial wall temperature profiles in monolithic catalysts can be measured and evaluated to provide corresponding concentration and reaction rate profiles With such data from several different runs, reliable kinetic model building is possible. A rate equation deduced for a fresh catalyst can be utilized t compute axial profiles of the catalytic activity from wall temperature profiles measured in partly deactivated samples. The whole procedure outlined in part I has been applied to the oxidation of carbon monoxide with air over Pt-based monolithic catalysts. Deactivation was performed by thermal aging, reversible poisoning by sulfur dioxide, and irreversible fouling by phosphorus compounds. In each case the kinetics was found non-separable. Tentative explanations for this are offered in terms of general mechanisms.
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