公开(公告)号：US20090131243A1

公开(公告)日：2009-05-21

申请号：US11995590

申请日：2006-07-15

申请人： Meike Wittrock ,  Ulrich Goebel ,  Thomas Kreuzer ,  Cristina Maria Casapu ,  Jan-Dierk Grunwaldt ,  Marek Maciejewski ,  Alfons Baiker

发明人： Meike Wittrock ,  Ulrich Goebel ,  Thomas Kreuzer ,  Cristina Maria Casapu ,  Jan-Dierk Grunwaldt ,  Marek Maciejewski ,  Alfons Baiker

IPC分类号： B01J38/06

CPC分类号： B01J38/06 ,  B01D53/9409 ,  B01J23/002 ,  B01J23/10 ,  B01J23/63 ,  B01J23/92 ,  B01J23/96 ,  B01J2523/00 ,  F01N3/035 ,  F01N3/0814 ,  F01N3/0842 ,  F01N3/0885 ,  F01N3/103 ,  F01N13/02 ,  F01N2430/08 ,  F01N2550/03 ,  F02B29/0437 ,  F02D41/0055 ,  F02D41/0275 ,  Y02A50/2322 ,  Y02T10/22 ,  B01J2523/25 ,  B01J2523/3712 ,  B01J2523/828

摘要： Nitrogen oxide storage catalysts are used for removing the nitrogen oxides present in the lean-burn exhaust gas of lean-burn engines. Here, the purifying action is based on the nitrogen oxides being stored in the form of nitrates by the storage material of the storage catalyst during a lean-burn operating phase of the engine and the previously formed nitrates being decomposed in a subsequent rich-burn operating phase of the engine and the nitrogen oxides which are being liberated again being reacted with the reducing exhaust gas constituents over the storage catalyst to form nitrogen, carbon dioxide and water. Storage catalysts are thermally aged by high temperatures. The aging is due to sintering of the catalytically active noble metal components of the catalyst and to formation of compounds of the storage components with the support materials. According to the invention, the formation of compounds of the storage materials can be largely reversed by treatment of the storage material with a gas mixture comprising nitrogen dioxide and/or carbon dioxide and water vapor at temperatures of from 300 to 500° C. The reactivation can be carried out either directly on the vehicle by setting appropriate exhaust gas conditions or during a routine service by removal of the catalyst from the vehicle and treatment with a gas mixture in an appropriate apparatus.

摘要翻译： 氮氧化物储存催化剂用于除去贫燃发动机的稀燃废气中存在的氮氧化物。 这里，净化作用是基于在发动机的稀薄燃烧操作阶段期间由储存催化剂的储存材料以硝酸盐的形式储存的氮氧化物，并且先前形成的硝酸盐在随后的富燃烧操作中被分解 再次释放的发动机和氮氧化物的相与还原废气成分反应，形成氮气，二氧化碳和水。 储存催化剂通过高温热老化。 老化是由于催化剂的催化活性贵金属组分的烧结以及用载体材料形成储存组分的化合物。 根据本发明，存储材料的化合物的形成可以通过在包含二氧化氮和/或二氧化碳和水蒸汽的气体混合物中在300-500℃的温度下处理储存材料而大大地逆转。再活化 可以直接在车辆上进行，通过设定适当的废气条件或者在例行服务期间通过从车辆中除去催化剂并在合适的装置中用气体混合物进行处理。