Engine exhaust catalysts containing zeolite and zeolite mixtures
AssigneeNanostellar, Inc.
InventorsKyle L. Fujdala, Timothy J. Truex
Life of this patent
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Abstract
A multi-layer emission control catalyst exhibits improved CO and HC reduction performance. The bottom layer includes a supported catalyst comprising platinum and palladium particles or palladium and gold particles. The middle layer includes zeolites. The top layer includes a supported catalyst comprising platinum and palladium particles. The use of zeolite mixture in the middle layer further improves CO and HC reduction performance in comparison with using zeolite of a single type. The use of a supported catalyst comprising palladium and gold particles in the bottom layer further improves CO and HC reduction performance in comparison with using a supported catalyst comprising platinum and palladium particles.
Claims18
An emission control catalyst comprising a substrate having first, second, and third washcoat layers coated thereon in a multi-layer configuration, wherein the first and third washcoat layers include supported precious group metal particles and the second washcoat layer is between the first washcoat layer and the third washcoat layer and contains zeolites of at least one type.
An emission control catalyst comprising:
- a substrate having first, second, and third washcoat layers coated thereon in a multi-layer configuration,
- wherein the first washcoat layer comprises supported platinum-palladium metal particles, and the third washcoat layer comprises supported platinum-palladium metal particles, and
- wherein the second washcoat layer is between the first washcoat layer and the third washcoat layer and contains zeolites of at least one type.
An emission control catalyst comprising:
- a substrate having first, second, and third washcoat layers coated thereon in a multi-layer configuration,
- wherein the first washcoat layer comprises supported palladium-gold metal particles, and the third washcoat layer comprises supported platinum-palladium metal particles, and
- wherein the second washcoat layer is between the first washcoat layer and the third washcoat layer and contains zeolites of at least one type.
Dependencies are inferred from the claim text.