CATALYSIS BY SUPPORTED AND UNSUPPORTED METALS AND ALLOYS.

Abstract

In complicated systems of reactions (even the most simple reactions are complicated by such side-reactions as self-poisoning and modification of the catalyst by the reaction mixture), the selectivity of the catalyst is not only determining the product patterns but also the activity in the reactions monitored. A point of importance is the question of the surface composition of alloys, prior to the reaction (in vacuum) or upon the reaction under the influence of corrosive chemisorption of reaction components, etc. Many of the reactions mentioned are structure sensitive (demanding) reactions. Alloying in combination with variations in the crystal size of a catalyst may open new ways to governing the mechanism of catalytic reactions.