Patent ID: 6022825
Filing Date: 2000-02-08
Classification: B01D,B01J,Y02T

Abstract:
An improved platinum group three-way catalyst composition comprising:(a) a high temperature catalyst support material;(b) a low temperature catalyst support material;(c) at least one platinum group metal;said (a) (b) and (c) being disposed in a catalytic layer on a non-porous catalyst support substrate,wherein the improvement comprises:(d) said composition also including an additive effective for the suppression of hydrogen sulfide emissions, said additive being disposed in a separate layer either under or over said catalytic layer or in the same layer as said catalytic layer, wherein when said additive is disposed in the same layer as said catalytic layer said additive is disposed in a physical structure that is segregated from the remaining components in said layer;said additive consisting essentially of a metal selected from the group consisting of Ba, Co, Fe, Mn, Ni, and oxides thereof.