US 7,922,988 B2Granted

Multilayered catalyst compositions

OwnerMichel Deeba, Stephan Siemund +5inventors

InventorsMichel Deeba, Stephan Siemund, Xinyi Wei, Stefan Kotrel, Knut Wassermann, Glenn Svoboda, Harold Rabinowitz

Life of this patent

Estimating the term…

Loading patent…

Abstract

A layered three-way conversion catalyst having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides is disclosed. Engine exhaust treatment system and methods of using the same are also provided. The catalytic material can be provided in layers such that a larger amount of oxygen storage component is provided in a downstream zone as compared to an upstream zone. For example, the upstream zone can be configured to have one, two, or three layers, and the downstream zone can be independently configured to have one, two, or three layers. In one or more embodiments, the catalyst supported on a carrier has three layers, where at least two of the layers are zoned to have an oxygen storage component being present in an upstream zone in an amount that is less than the oxygen storage component present in the downstream zone.

Claims15

Dependent claims

An exhaust gas treatment system comprising:

a catalytic material having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides and having an upstream zone and a downstream zone deposited on a carrier;
wherein in the upstream zone, the catalytic material comprises:
an inner layer on the carrier, the inner layer comprising a support and a palladium component;
an outer layer above the inner layer, the outer layer comprising a support and a rhodium component;
and
a first oxygen storage component located in the inner layer, the outer layer, or both;
wherein in the downstream zone, the catalytic material comprises:
an inner layer on the carrier, the inner layer comprising a support and a palladium component;
an outer layer above the inner layer, the outer layer comprising a support and a rhodium component;
and
a second oxygen storage component located in the inner layer, the outer layer, or both such that the second oxygen storage component is present in an amount that is greater than the amount of the first oxygen storage component.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/609,622Filed 30 Oct 2009 · continuation in part
Priority: 9 Aug 2007
Published: US 2010/0104491 A129 Apr 2010
Granted: 12 Apr 2011
Term ends: Not estimatedThe source records don’t support an estimate.

Classification15 codes

B01D 53/945
Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]:…
B01D 53/9472
With catalysts positioned on one brick: in different zones
B01D 53/9477
Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one…:…
F01N 3/2803
Construction of catalytic reactors: characterised by structure, by material or by manufacturing of catalyst support

Family

Application11/836,397Parent of this continuation-in-part · filed 9 Aug 2007
US 2010/0104491 A1Pre-grant publication · published 29 Apr 2010
US 7,622,096 B2Parent of this continuation-in-part
US 2009/0041643 A1Published application
US 7,922,988 B2This patent

From the US filing history. Foreign family members aren’t listed.