abstract |
A catalyst composition includes a carrier on which is disposed a catalytic material which may optionally be provided in discrete first and second coats. The catalyst material contains, e.g., in the first coat, a refractory inorganic oxide first support having a catalytically effective amount of platinum dispersed thereon. The catalyst material also contains, e.g., in the second coat, a stabilized alumina second support having a catalytically effective amount of a second platinum catalyst dispersed thereon, and a third catalyst component which contains a zirconia-stabilized third support, e.g., alumina, having dispersed thereon catalytically effective amounts of rhodium and palladium. A method of treating internal combustion engine exhaust gases with the catalyst composition is also disclosed. |