Reducing coking over Ag/Al2O3 HC-SCR catalyst
    1.
    发明授权
    Reducing coking over Ag/Al2O3 HC-SCR catalyst 有权
    在Ag / Al2O3 HC-SCR催化剂上还原焦化

    公开(公告)号:US08387367B2

    公开(公告)日:2013-03-05

    申请号:US12084997

    申请日:2006-11-09

    IPC分类号: F01N3/00

    摘要: The present invention relates to a method of reducing coking over a Ag/Al2O3 hydrocarbon selective catalytic reduction catalyst in an exhaust stream of a lean burn internal combustion engine, the exhaust stream including hydrocarbon and NOx. The method includes controlling the hydrocarbon to molar NOx ratio of the exhaust stream so as to be within certain limits at certain temperatures. An exhaust system for a lean burn engine suited to the above method, and a lean burn internal combustion engine, or a vehicle or stationary power source including such an exhaust system are also included.

    摘要翻译: 本发明涉及一种在稀燃内燃机的废气流中的Ag / Al 2 O 3选择性催化还原催化剂上还原焦化的方法,所述废气流包括烃和NOx。 该方法包括在某些温度下控制烃与排气流的摩尔NOx比以达到某一极限。 还包括适用于上述方法的稀薄燃烧发动机的排气系统,以及稀燃燃烧内燃机或包括这种排气系统的车辆或固定动力源。

    EXHAUST GAS AFTERTREATMENT
    3.
    发明申请
    EXHAUST GAS AFTERTREATMENT 有权
    排气净化

    公开(公告)号:US20120117948A1

    公开(公告)日:2012-05-17

    申请号:US13112571

    申请日:2011-05-20

    IPC分类号: F01N3/18 F01N3/10

    摘要: A method to improve NOx reduction in diesel engine exhausts by selective catalytic reduction using reductants comprising hydrocarbons, comprising passing the exhaust gases through a series of zones, said zones comprising a first zone in which a first catalyst is located that promotes HC SCR, to yield a first product gas; a second zone through which the first product gas is passed and in which a second catalyst is located that promotes the H2-promoted HC SCR reaction to produce a second product gas and a third zone through which the second product gas is passed and in which a third catalyst is located that promotes CO/H2 SCR to yield a final, NOx-depleted, exhaust gas, and admixing a reformate gas comprising CO and H2 with one or more of the exhaust gases, the first product gas and the second product gas. The use of the series of catalysts offers a sound alternative to urea-based SCR, without requiring a source and storage of urea.

    摘要翻译: 一种通过使用包含烃的还原剂通过选择性催化还原来改善柴油发动机排气中的NOx还原的方法,包括使废气通过一系列区域,所述区域包括第一区域,其中第一催化剂位于促进HC SCR的第一区域,以产生 第一产品气; 第二区域,第一产物气体通过该第二区域,并且其中定位有第二催化剂的第二区域,其促进H 2促进的HC SCR反应以产生第二产物气体和第二产物气体通过的第三区域,其中 定位第三催化剂,其促进CO / H 2 SCR以产生最终的NO x贫化废气,并且将包含CO和H 2的重整气体与一种或多种废气,第一产物气体和第二产物气体混合。 使用一系列催化剂提供了一种可靠的尿素SCR替代品,而不需要尿素的来源和储存。