摘要:
A sulfur tolerant oxidation catalyst with appreciable NO and HC oxidation capabilities has been developed for use in any component of an exhaust aftertreatment system for a lean-burn engine where the oxidation of at least NO is desired. Several non-exclusive examples of such components where the oxidation catalyst may be employed include a DOC and a LNT. The oxidation catalyst may comprise perovskite oxide particles that support palladium particles. The ability of the palladium supported perovskite oxide particles to concurrently oxidize NO and HC's can significantly diminish or altogether eliminate the use of platinum in the exhaust aftertreatment system for at least NO oxidation. The oxidation catalyst, moreover, may exhibit superior thermal durability and better NO and HC oxidation activities than platinum in some instances.
摘要:
A sulfur tolerant oxidation catalyst with appreciable NO and HC oxidation capabilities has been developed for use in any component of an exhaust aftertreatment system for a lean-burn engine where the oxidation of at least NO is desired. Several non-exclusive examples of such components where the oxidation catalyst may be employed include a DOC and a LNT. The oxidation catalyst may comprise perovskite oxide particles that support palladium particles. The ability of the palladium supported perovskite oxide particles to concurrently oxidize NO and HC's can significantly diminish or altogether eliminate the use of platinum in the exhaust aftertreatment system for at least NO oxidation. The oxidation catalyst, moreover, may exhibit superior thermal durability and better NO and HC oxidation activities than platinum in some instances.
摘要:
A method for catalytic oxidation of NO to NO2 in the sulfur-containing exhaust gases of lean-burn engines, such as diesel engines is disclosed. The catalysts are oxide perovskites with a credible likelihood of being sulfur-tolerant.
摘要:
A method for catalytic oxidation of NO to NO2 in the sulfur-containing exhaust gases of lean-burn engines, such as diesel engines is disclosed. The catalysts are oxide perovskites with a credible likelihood of being sulfur-tolerant.
摘要:
Certain metal-exchanged SUZ-4 zeolites have been prepared that have catalytic activity for the reduction of NOx in the exhaust of a hydrocarbon or alcohol fueled engine operated under fuel lean conditions. Initially the SUZ-4 zeolite contains alkali metal cations such as Li+, Na+, K+ and/or Cs+. These alkali metal cation-containing zeolites are partially exchanged with at least one of copper (II), silver (I), iron (III) or cobalt (II) ions. The resulting partially exchanged SUZ-4 zeolites display such activity and are stable under extreme hydrothermal aging conditions.
摘要:
Catalysts, systems and methods are described to reduce NOx emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having a catalyst comprising silver and a platinum group metal on a particulate alumina support, the atomic fraction of the platinum group metal being less than or equal to about 0.25. Methods of manufacturing catalysts are described in which silver is impregnated on alumina particles.
摘要:
A method and apparatus are described to selectively reduce NOx emissions of an internal combustion engine. An exhaust aftertreatment system comprises an injection device operative to dispense a hydrocarbon reductant upstream of a silver-alumina catalytic reactor device. A control system determines a NOx concentration and hydrocarbon/NOx ratio based upon selected parameters of the exhaust gas feedstream and dispenses hydrocarbon reductant during lean engine operation. Included is a method to control elements of the feedstream during lean operation. The hydrocarbon reductant may comprise engine fuel.
摘要翻译:描述了一种方法和装置来选择性地减少内燃机的NOx排放。 排气后处理系统包括一个注入装置,其可操作以在银 - 氧化铝催化反应器装置上游分配烃还原剂。 控制系统基于废气进料流的选定参数确定NO x SO 2浓度和烃/ NO x SO 2比例,并在稀薄发动机运转期间分配碳氢化合物还原剂。 包括在精炼操作期间控制进料流的元素的方法。 烃还原剂可以包括发动机燃料。
摘要:
A method and apparatus are described to selectively reduce NOx emissions of an internal combustion engine. An exhaust aftertreatment system includes an injection device operative to dispense a hydrocarbon reductant upstream of a silver-alumina catalytic reactor device. A control system determines a NOx concentration and hydrocarbon/NOx ratio based upon selected parameters of the exhaust gas feedstream and dispenses hydrocarbon reductant during lean engine operation. Included is a method to control elements of the feedstream during lean operation. The hydrocarbon reductant may include engine fuel.
摘要:
Catalysts, systems and methods are described to reduce NOx emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having a catalyst comprising silver and a platinum group metal on a particulate alumina support, the atomic fraction of the platinum group metal being less than or equal to about 0.25. Methods of manufacturing catalysts are described in which silver is impregnated on alumina particles.
摘要:
Certain metal-exchanged SUZ-4 zeolites have been prepared that have catalytic activity for the reduction of NOx in the exhaust of a hydrocarbon or alcohol fueled engine operated under fuel lean conditions. Initially the SUZ-4 zeolite contains alkali metal cations such as Li+, Na+, K+ and/or Cs+. These alkali metal cation-containing zeolites are partially exchanged with at least one of copper (II), silver (I), iron (III) or cobalt (II) ions. The resulting partially exchanged SUZ-4 zeolites display such activity and are stable under extreme hydrothermal aging conditions.