Exhaust emission control system having a nitrogen oxide adsorber and method for desulfating the nitrogen oxide adsorber

摘要

An exhaust emission control system having a nitrogen oxide adsorber and a desulfating device, and a method for desulfating a nitrogen oxide absorber. The desulfating device is managed so as to establish an oscillatingly rich and lean exhaust gas composition during a respective desulfating operation, and contain an oxygen accumulator downstream from the nitrogen oxide adsorber. The nitrogen oxide adsorber is effectively desulfated by way of a corresponding desulfating method, and released sulfur compounds are thereby simultaneously oxidized. The exhaust emission control systems can be utilized, for example, with a motor vehicle internal combustion engine.