palladium catalyst for the methanoxidation washcoats in exhaust gases from natural gas vehicles

摘要

The invention provides a catalyst which can convert methane, carbon monoxide, and nitrogen oxides in lean, stoichiometric, and rich air/fuel environments. Support (A) of the catalyst comprises an alumina support impregnated with Pd providing lean methane conversions and support (B) of the catalyst comprises ceria/lanthana/alumina impregnated with Pd providing stoichiometric methane conversion. Rhodium may be substituted for all or part of the Pd on an alumina support.