Improving the poison resistance of supported catalysts

Abstract

This paper discusses the poison resistance of supported catalysts, in which the poison reacts both with the active component and the catalyst support. For such catalysts, the net rate of the poisoning reaction can be selectively manipulated with respect to the net rate of the main reaction in such a manner that a catalyst with improved poison resistance is obtained. The above statements are illustrated by diffusion-limited lead and phosphorus poisoning experiments using alumina-supported noble metal catalysts. By modifying the pore structure, support surface area, and noble metal impregnation depth of these catalysts, improvements in activity and poison resistance have been attained for automobile exhaust emission-control applications.