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:
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 has a base catalyst layer containing platinum and barium as precious metal supported by alumina and an over catalyst layer containing platinum and rhodium as precious metal supported by zeolitr. The platinum and rhodium in the over catalyst layer activate NOx and HC so as to make them more reactive in terms of energy, and the barium in the base catalyst layer makes the platinum be more dispersive in the base catalyst layer. Under the existence of dispersive platinum, NOx in exhaust gas is decomposed and purified by reaction with reactive NO.sub.2 and partially oxidized HC generated in the over catalyst layer.
摘要:
An exhaust gas purifying catalyst is provided by coating a slurry of a mixture of a powdered first catalyst provided by carrying Pt on a mixture of alumina and ceria and a powdered second catalyst provided by carrying Rh on manganese oxide on a support member and then impregnating the coated layer with a solution of barium.
摘要:
An exhaust gas purifying system includes an exhaust gas purifying catalyst having a nitrogen oxide absorbing material which is installed in an exhaust line of an engine and performs split fuel injection to inject fuel directly into each combustion chamber partly during a suction stroke and partly during a compression stroke to provide and supply an increased amount of carbon monoxide to the nitrogen oxide absorbing material so as thereby to desorb sulfur oxides from the nitrogen oxide absorbing material.
摘要:
Disclosed is a particulate filter, which is adapted to be disposed in an exhaust passage of an engine to trap particulate matter contained in exhaust gas discharged from the engine. The particulate filter comprises a filter body having a porous partition wall which defines a plurality of exhaust gas channels allowing the exhaust gas to pass therethrough, and a catalyst layer formed on a surface of the porous partition wall. The catalyst layer includes a Zr-based composite oxide which contains zirconium (Zr), and a rare-earth metal except cerium, wherein a content ratio of an oxide of the non-cerium rare-earth metal to a total amount of ZrO2 and the oxide of the non-cerium rare-earth metal in the Zr-based composite oxide is set in the range of greater than 33 mol % to less than 40 mol %. The particulate filter of the present invention can achieve a higher PM burning rate to burn PM within a shorter period of time. In addition, the higher PM burning rate makes it possible to provide enhanced fuel economy performance in an engine designed to perform a post-injection control.
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:
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:
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.