Internal combustion engine with exhaust-gas purification system, and method for purifying the exhaust gas from an internal combustion engine

USRE46512E1 · kind E1 · reissue

Assignee

• Daimler AG · DE

Inventors

• Thomas Beckmann · Chapel Hill, US
• Alexander Massner · Eßlingen, DE

Key dates

• Filing date: Sep 7, 2011
• Grant date: Aug 15, 2017
• Expiry date: Sep 7, 2031

Classification

• Technology area (CPC —): General

Abstract

An exhaust-gas purification system and method are provided for an internal combustion engine having an NOx storage catalytic converter and a downstream SCR catalytic converter. The NOx storage catalytic converter can be supplied in a first operating mode with an oxidizing exhaust gas and in a second operating mode with a reducing exhaust gas. A third operating mode is provided between the first operating mode and the second operating mode, in which an exhaust gas which has a lower content of oxidizing constituents than the first operating mode and a lower content of reducing constituents than the second operating mode can be supplied to the NOx storage catalytic converter to improve NH3 production at the start of converter regeneration.