Reorganisation of nickel under steam reforming conditions

Abstract

The reorganisation of nickel films supported on silica has been studied under conditions pertinent to the steam reforming of propylene. Examination of reorganisation under steam reforming conditions, and in the presence of individual reactants and products, shows that hydrogen has a large effect on metal restructuring. The kinetics of the process are studied and are shown to be consistent with theoretical predictions based on the concept that the mechanism of nickel reorganisation involves surface self diffusion of the metal. The effect of hydrogen pressure is complex and is tentatively explained in terms of the formation of different nickel hydrides. If carbon is deposited on the metal, reorganisation of the films is found to be slow.