Catalyst compositions, catalytic articles, systems and processes using protected molecular sieves

摘要

Described are catalyst compositions, catalytic articles, methods of manufacturing catalytic articles and exhaust gas treatment systems and methods that utilize the catalytic articles. The catalyst composition comprises an oxidation catalyst comprising a washcoat layer including a platinum group metal supported on a refractory metal oxide support and porous molecular sieve particles having internal pores, the molecular sieve particles protected by a protecting material selected from an organic wax encapsulating the molecular sieve particles, a polymer encapsulating the molecular sieve particles, an inorganic oxide deposited on the surface of the molecular sieve particles, or an organic compound filling the internal pores of the molecular sieve particles, wherein the protecting material prevents interaction of the molecular sieve particles with the platinum group metal.

主权项

1. A catalyst composition for the treatment of exhaust gas from an internal combustion engine containing hydrocarbons, carbon monoxide and nitrogen oxides, wherein the catalyst composition comprises an oxidation catalyst comprising a washcoat layer including a platinum group metal supported on a refractory metal oxide support and further including porous molecular sieve particles having internal pores, the molecular sieve particles protected by a protecting material selected from an organic wax encapsulating the molecular sieve particles, a polymer encapsulating the molecular sieve particles, or an organic compound filling the internal pores of the molecular sieve particles, wherein the protecting material prevents interaction of the molecular sieve particles with the platinum group metal.