Manganese-Containing Diesel Oxidation Catalyst

摘要

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, an oxidation catalyst composite including a first washcoat comprising a zeolite, Pt, and first refractory metal oxide support containing manganese, a second washcoat comprising a second refractory metal oxide support, a Pt component and a Pd component, and a third washcoat comprising palladium and a rare earth oxide component is described.

主权项

1. An oxidation catalyst composite for abatement of exhaust gas emissions from a lean burn engine comprising:
a carrier substrate having a length, an inlet end and an outlet end, an oxidation catalyst catalytic material on the carrier, the oxidation catalyst catalytic material comprising a first washcoat including a zeolite, Pt, and a first refractory metal oxide support containing Mn;
a second washcoat including a second refractory metal oxide support, a platinum (Pt) component and a palladium (Pd) component in a ratio of Pt:Pd in the range of about 10:1 to 1:10; anda third washcoat comprising palladium and a rare earth oxide component, the third washcoat being substantially free of platinum; wherein the oxidation catalyst composite is effective to abate hydrocarbon and carbon monoxide, and to oxidize NO to NO2 in the lean burn engine exhaust.