Catalyst arrangement and method of purifying the exhaust gas of internal combustion engines operated under lean conditions

US7799298B2 · kind B2 · utility

Assignee

• UMICORE AG & CO. KG · DE

Inventors

• Marcus Pfeifer · Mannheim, DE
• Nicola Soeger · Nidderau, DE
• Yvonne Demel · Frankfurt am Main, DE
• Tobias Kuhl · Hanau, DE
• Paul Spurk · Weiterstadt, DE
• Jurgen Gieshoff · Bad Orb, DE
• Egbert Lox · Hanau, DE
• Thomas Kreuzer · Karben, DE

Key dates

• Filing date: Jul 29, 2004
• Grant date: Sep 21, 2010
• Expiry date: Mar 4, 2027

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to a catalyst arrangement for purifying the exhaust gases of internal combustion engines operated under lean conditions. It is proposed that a thinwalled, porous carrier be coated on one side with a nitrogen oxide storage catalyst and on the other side with an SCR catalyst. When the exhaust gas is passed through the catalytic coatings and the support material, a significant improvement in the nitrogen oxide conversion is achieved compared to a series arrangement of the catalysts on separate carriers. Wall flow filters have been found to be useful as thin-walled carriers.