초록 ▼

A catalyst composition and layered catalyst composite of the type generally referred to as a three-way conversion catalyst having the capability of substantially simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides. The catalyst composition

A catalyst composition and layered catalyst composite of the type generally referred to as a three-way conversion catalyst having the capability of substantially simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides. The catalyst composition comprises at least two supports, at least one first precious metal component. There is at least one lanthana stabilized alumina support, and at least one refractory oxide unstabilized support. The composition further comprises at least one precious metal component located on the lanthana stabilized alumina support and the unstabilized support. There is an oxygen storage composition comprising, 40 to 80 weight percent of a diluent component, 10 to 60 weight percent of a cerium component, 1 to 15 weight percent of a neodymium component, and 1 to 15 weight percent of a praseodymium component. The composition also comprises at least one alkaline earth metal stabilizer; and a zirconium component.

대표청구항 ▼

[ What is claimed is:] [1.] A layered catalyst composite comprising a first layer and a second layer:the first layer comprising:at least one first layer lanthana stabilized alumina support comprising a solid solution comprising lanthana and alumina;at least one first layer unstabilized refractory ox

[ What is claimed is:] [1.] A layered catalyst composite comprising a first layer and a second layer:the first layer comprising:at least one first layer lanthana stabilized alumina support comprising a solid solution comprising lanthana and alumina;at least one first layer unstabilized refractory oxide support, wherein the refractory oxide is not in solid solution with a rare earth component;at least one first layer precious metal component located on the lanthana stabilized alumina support and the unstabilized refractory oxide support;a first layer oxygen storage composition;at least one first layer stabilizer; anda first layer zirconium compound; andthe second layer comprising:at least one second layer support;a second layer oxygen storage composition is a composite which comprises,40to 80 weight percent of a diluent component,10 to 60 weight percent of a cerium component,1 to 15 weight percent of a neodymium component, and1 to 15 weight percent of a praseodymium component;a second layer precious metal component; anda second layer zirconium component.