Patent ID: 6348430
Filing Date: 2002-02-19
Classification: B01D,B01J,Y02T,Y10S

Abstract:
An exhaust gas treatment catalyst for internal combustion engines comprising palladium and rhodium and two catalytically active layers on a carrier structure,wherein a first layer on said carrier structure comprises particulate aluminum oxide, optionally stabilized, and at least one particulate oxygen storage material selected from the group consisting of cerium oxide, cerium/zirconium and zirconium/cerium mixed oxides, and the first layer further comprises at least one highly dispersed alkaline earth metal oxide and palladium; and a second layer, which is in direct contact with the exhaust gas, and comprises particulate aluminum oxide and at least one particulate oxygen storage material selected from the group consisting of cerium oxide, cerium/zirconium and zirconium/cerium mixed oxides, and wherein rhodium is supported on either of said at least one oxygen storage material of the second layer or on part of said aluminum oxide of the second layer while palladium in said first layer is in close contact with all constituents of the first layer.