Reactions of hydrocarbons on alumina-supported Pt–Ir bimetallic catalysts. Part 1.—Exchange of methane and cyclopentane with deuterium, and hydrogenolysis of butane, pentane and cyclopentane

Abstract

Exchange reactions with deuterium of cyclopentane (303 K) and of methane (473 K) and the hydrogenolysis of n-butane, n-pentane and cyclopentane have been studied on a series of alumina-supported Pt–Ir catalysts. Metal composition had little effect on the activity of the catalysts for the exchange reactions but influenced the character of the reactions in a regular manner. Rates of hydrogenolysis increased with iridium content, and the change was > 100 for n-butane but only 10 for cyclopentane. The main reaction with cyclopentane was ring-opening, but the extent of further hydrogenolysis increased with iridium content in a manner that suggested the possible requirement of ensembles of three iridium atoms.