Patent ID: 6087298
Filing Date: 2000-07-11
Classification: B01D,B01J,F01N,Y02A,Y02T

Abstract:
An exhaust gas treatment catalytic article comprising: an upstream catalytic zone and at least one downstream catalytic zone, the upstream catalytic zone comprising:an upstream composition comprising;a first upstream support, andat least one first upstream palladium component, there being a sufficient amount of the upstream palladium component to result in a 50 percent conversion at 200.degree. C. to 350.degree. C. for the oxidation of hydrocarbons, andwherein the upstream composition has substantially no oxygen storage components; andthe downstream catalytic zone comprising:a first downstream layer comprising;a first downstream support,a first downstream precious metal component,a second downstream layer comprising;a second downstream support,a second downstream precious metal component,wherein at least one of the first and second downstream layers comprises a palladium component; andwherein the upstream composition has a lower light-off temperature than the downstream composition.