Exhaust-gas aftertreatment device with nitrogen oxide storage catalytic converter, and operating method therefor

US7174705B2 · kind B2 · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Klaus Binder · Munich, DE
• Josef Gunther · Marbach am Neckar, DE
• Andreas Hertzberg · Markgröningen, DE
• Brigitte Konrad · Blaustein, DE
• Bernd Krutzsch · Köngen, DE
• Heinz-Jost Ölschlegel · Notzingen, DE
• Stefan Renfftlen · Eislingen/Fils, DE
• Dirk Voigtlander · Ditzingen, DE
• Michel Weibel · Großburgwedel, DE
• Marko Weirich · Mannheim, DE
• Gunter Wenninger · Stuttgart, DE
• Rolf Wunsch · Malsch, DE

Key dates

• Filing date: Jan 9, 2004
• Grant date: Feb 13, 2007
• Expiry date: Jan 9, 2024

Classification

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

Abstract

An internal combustion engine includes an exhaust-gas aftertreatment device, and an operating method is for operating the internal combustion engine. The internal combustion engine is operable with a lean mixture and a rich mixture, the internal combustion engine having an exhaust-gas aftertreatment device, which includes a nitrogen oxide storage catalytic converter and a particle filter. When lean exhaust gas flows through the nitrogen oxide storage catalytic converter, it removes nitrogen oxides from the exhaust gas by storing them, and, when reducing exhaust gas flows through the nitrogen oxide storage catalytic converter, it produces ammonia through reduction of stored and/or supplied nitrogen oxides and releases it to the exhaust gas. Downstream from the nitrogen oxide storage catalytic converter, the exhaust-gas aftertreatment device includes a SCR catalytic converter, which reduces nitrogen oxides contained in the exhaust gas, using ammonia produced by the nitrogen oxide storage catalytic converter.