Patent ID: 7501098
Filing Date: 2009-03-10
Classification: B01D,B01J,Y02A,Y02T

Abstract:
1. An exhaust gas treatment article comprising: a catalyst, an upstream EGO or air/fuel ratio sensor and a downstream EGO sensor, wherein the catalyst comprises: (a) a carrier; (b) a first washcoat layer deposited on the carrier, said first washcoat layer comprising substantially only at least one refractory metal oxide; (c) a second washcoat layer deposited on the first washcoat layer, said second washcoat layer comprising substantially only at least one oxygen storage component and at least one binder therefor; and (d) a third washcoat layer deposited on the second washcoat layer, said third washcoat layer comprising at least one washcoat layer of one or more platinum group metal components supported on a refractory metal oxide support, wherein the amount of oxygen storage component in the second layer is present in an amount sufficient so that deterioration of its oxygen storage capacity can be correlated with deterioration of the catalyst's ability to reduce hydrocarbons, carbon monoxides or nitrogen oxides in the exhaust gas.