摘要:
In the exhaust gas purifying catalyst (3), palladium is contained as a catalytic component and cerium oxide and (Ce, Pr) compound oxide is contained as a promoter. Now, the weight ratio of cerium oxide to (Ce, Pr) compound oxide is set between 9/1 and 7/3, and the ratio of praseodymium to cerium in the (Ce, Pr) compound oxide is set between 3 mol % and 50 mol %. In this way, because in this exhaust gas purifying catalyst (3), palladium with high low-temperature activity is used for a catalytic component, the exhaust gas purifying performance at low temperature is improved. And because cerium oxide and (Ce, Pr) compound oxide improves catalytic activity of palladium at high temperature, the exhaust gas purifying performance at high temperature, in particular, NOx purifying performance, is improved.
摘要:
An exhaust gas purifying catalyst (3) has an inner catalytic layer (5) fixed on a carrier (4). In the inner catalytic layer (5), there are held a palladium component, platinum component and a rhodium component by a base material containing an alumina component composed of alumina impregnated with lanthanum. Further, the exhaust gas purifying catalyst (3) has an outer catalytic layer (6) formed on the inner catalytic layer (5). In the outer catalytic layer (6), a palladium component is held by a base material which contains an alumina component, an oxide complex of ceria and zirconia and a magnesium component.
摘要:
An exhaust gas emission control catalyst includes an under catalyst layer containing at least one of barium and lanthanum and an over catalyst layer containing an agent for absorbing water in a gas, at least one of the under catalyst layer and over catalyst layer containing catalytic metal.
摘要:
An exhaust gas emission control catalyst includes an under catalyst layer containing at least one of barium and lanthanum and an over catalyst layer containing an agent for absorbing water in a gas, at least one of the under catalyst layer and over catalyst layer containing catalytic metal.
摘要:
A catalyst comprises an HC trapping material that is capable of trapping HC in an exhaust gas under low temperatures and releasing HC with a raise in temperature and catalytic material containing a Ce—Pr double oxide capable of oxidizing and purifying HC from the HC trapping material with a high efficiency.
摘要:
An exhaust gas emission control catalyst includes an under catalyst layer containing at least one of barium and lanthanum and an over catalyst layer containing an agent for absorbing water in a gas, at least one of the under catalyst layer and over catalyst layer containing catalytic metal.
摘要:
A catalyst for lowering NOx concentration in an exhaust gas is disposed in an exhaust gas passage of an engine. The catalyst composed of a catalyst layer formed on a substrate. A NOx absorber that absorbs NOx when an oxygen concentration in the exhaust gas is high and releases NOx when the oxygen concentration drops, and a precious metal for reducing NOx are supported on a support material as catalyst components, and the NOx absorber includes Ba, K, Sr, and Mg. By lowering the oxygen concentration in the exhaust gas and raising a temperature of the NOx absorber when sulfur component is absorbed excessively in the NOx absorber, it is possible to regenerate the catalyst from the S poisoning.
摘要:
Disclosed is a particulate filter 10, which comprises a filter body 8 including a plurality of filter segments F1, F2 joined to each other by a joining material 7, wherein each of the filter segments includes a plurality of inflow cells each having a closed end on a downstream side in an exhaust-gas flow direction, and a plurality of outflow cells each having a closed end on an upstream side in the exhaust-gas flow direction. The filter segments include a first filter segment located in a central region of the particulate filter and designed to form each of the inflow cells to have an opening area approximately equal to that of each of the outflow cells, and a second filer segment located in at least a part of an outer peripheral region of the particulate filter and designed to form each of the inflow cells to have an opening area greater than that of each of the outflow cells. The present invention can keep the central region of the particulate filter from becoming overheated during a particulate-filter regeneration process, while suppressing a pressure loss.
摘要:
Disclosed is a catalytic material for purifying an exhaust gas component. The catalytic material comprises a composite oxide which contains, as essential components, zirconium (Zr) and neodymium (Nd), and further contains a rare-earth metal R other than cerium (Ce) and neodymium (Nd), wherein each of the zirconium, neodymium and rare-earth metal R constituting the composite oxide is contained, in the form of oxide, in such a manner that a ratio of Nd2O3/(ZrO2+Nd2O3+RO) is 3 mol % or more, and a ratio of (Nd2O3+RO)/(ZrO2+Nd2O3+RO) is 33 mol % or less. The catalytic material of the present invention can oxidize/burn PM in a short period of time, while suppressing CO emission during the burning of the PM, and can achieve further enhanced NOx conversion performance.
摘要翻译:公开了一种用于净化废气成分的催化材料。 催化剂材料包含含有锆(Zr)和钕(Nd)作为必要成分的复合氧化物,并且还包含除了铈(Ce)和钕(Nd)之外的稀土金属R,其中每个锆 构成复合氧化物的钕和稀土类金属R以氧化物的形式含有Nd 2 O 3 3(ZrO 2)的比例 < 2> 2 + Nd 2 O 3 + RO)的摩尔比为3摩尔%以上,(Nd 2 N 2 O 2 + > O 3 + RO)/(ZrO 2 + Nd 2 O 3 + RO)为33摩尔% 或更少。 本发明的催化剂材料可在短时间内氧化/燃烧PM,同时在PM燃烧过程中抑制CO排放,并可进一步提高NOx转化性能。
摘要:
In at least part of a catalyst layer of a particulate filter, a second catalyst part is exposed on the surface of the catalyst layer to overlie a first catalyst part, the first catalyst part contains Pt-carried activated alumina particles, the second catalyst part contains ZrNd-based mixed oxide particles containing a rare earth metal M and at least one of the first catalyst part and the second catalyst part further contains CeZr-based mixed oxide particles containing a rare earth metal R.