Diesel oxidation catalyst
AssigneeEngelhard Corporation
InventorsKenneth E. Voss, Joseph C. Dettling, Stanley Roth, Ramesh Kakwani, Yiu Kwan Lui, Alexander Gorel, Gary W. Rice
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Abstract
The present invention relates to a method and article for treating a diesel engine exhaust stream. The stream is contacted with an upstream catalytic composition having a cerium component and/or a zeolite component to reduce the quantity and amount of the particulate matter in the exhaust stream. The stream passes from the upstream catalytic composition to a particulate filter located downstream from the upstream catalytic composition.
Claims24
A method for treating a diesel engine exhaust stream containing particulate matter comprising the steps of:
- contacting the stream with an upstream catalytic composition comprising an acidic zeolite component to reduce the quantity and amount of the particulate matter;
- passing the stream from the upstream catalytic composition to a particulate filter located downstream from the upstream catalytic composition.
The method as recited in claim 2 wherein the diesel engine exhaust stream further comprises nitrogen oxides, carbon monoxide, gaseous hydrocarbons, the upstream catalyst component further comprises at least one precious metal catalyst component;
- and the method further comprises:
- reducing at least some of the nitrogen oxides to nitrogen in the presence of the precious metal component;
- and
- oxidizing the hydrocarbons and carbon monoxide.
Dependencies are inferred from the claim text.