The present invention provides for novel poisoning-resistant catalysts used for automobile exhaust gas treatment systems. To alleviate the detrimental affects of engine oil and/or fuel additive poisoning the present invention provides for an overcoat layer comprising a porous refractory oxide and one or more base metal oxides, which is coated over one or more precious metal containing washcoat layers. The overcoat of the present invention prevents phosphorous as well as other poisoning deposits, from fouling and/or negatively interacting with the underlying precious metal containing washcoats. In an alternative embodiment, the present invention provides for the coating of the upstream end of a catalytic member by the overcoat layer, thereby creating an upstream poison capture zone.

 
Web www.patentalert.com

< Reduction of oxides of nitrogen in a gas stream using boron-containing molecular sieve CHA

< Air pollutant control system and method for removing mercury in flue gas

> Method and device for controlling exhaust emission from internal combustion engine

> Treatment of engine exhaust using molecular sieve SSZ-75

~ 00620