摘要:
Provided is an exhaust purification system for an internal combustion engine. The exhaust purification system comprising: a NOX purifying catalyst arranged in an exhaust passage of the internal combustion engine, wherein the NOX purifying catalyst comprises a base metal supported on a catalyst support; an oxygen sensor arranged at the downstream side of the NOX purifying catalyst in the exhaust passage; and an air-fuel, ratio control means for controlling the air-fuel ratio of exhaust gas flowing into the NOX purifying catalyst; wherein when the NOX purifying catalyst suffers from predetermined oxygen poisoning, the air-fuel ratio control means controls the air-fuel ratio of the exhaust gas, which flows into the NOX purifying catalyst, to a first air-fuel ratio wherein the first air-fuel ratio is richer than a theoretical air-fuel ratio, and then the air-fuel ratio control means switches the air-fuel ratio of the exhaust gas, which flows into the NOX purifying catalyst, to a second air-fuel ratio on the basis of an output value from the oxygen sensor wherein the second air-fuel ratio is leaner than the first air-fuel ratio.
摘要:
The present invention relates to a catalyst for purification of nitrogen oxides, the catalyst comprising a solid in which Au and Fe atoms exist in a state of being close. In accordance with the present invention, a catalyst that can demonstrate NOx purification performance at low temperatures and/or in an oxidative atmosphere is provided.
摘要:
[Problem] The present invention provides a NOx purification catalyst which utilizes Ag as one of the catalyst components and exhibits NOx purification performance without adjustment to a special exhaust gas composition, as well as a method of producing the same.[Means for Solution] The present invention provides a nitrogen oxide purification catalyst in which particulates are supported on a metal oxide carrier, wherein the aforementioned particulates consist of Ag and Ni and the aforementioned Ag and Ni are at least partially alloyed. Also provided is a method of producing the aforementioned catalyst, comprising the step of preparing a colloidal suspension in which the ratio of Ag is 10 to 90 at % with respect to the total amount of Ag and Ni.
摘要:
An exhaust gas purification system provided with an NOX purification catalyst reducing the amount of use of precious metals and/or able to exhibit an NOX purification performance at a low temperature and/or in an oxidizing atmosphere and having an NOX purification performance even for an exhaust gas composition containing hydrocarbons and oxygen together with a low temperature and/or oxidizing atmosphere, that is, an exhaust gas purification system provided with an NOX purification catalyst provided in an exhaust gas passage and comprised of carrier particles on which nanoparticles in which gold atoms and nickel atoms are included in a state in close proximity are carried and an oxidation catalyst oxidizing hydrocarbons in exhaust gas at a position at an upstream side of the NOX purification catalyst.
摘要:
The present invention relates to a catalyst able to exhibit an NOx purification performance at a low temperature and/or in an oxidizing atmosphere, that is, a nitrogen oxides purification catalyst composed of particles having an average particle size of 0.2 to 100 nm and including gold atoms and iron atoms in a state of close proximity.
摘要:
An exhaust emission control apparatus that is used with an internal combustion engine to use both a NOx retention member and a catalyst while avoiding a decrease in the exhaust gas purification capacity. A NOx occlusion reduction type catalyst is placed in an exhaust path of an internal combustion engine. The NOx occlusion reduction type catalyst includes a base material. The base material includes an exhaust inflow cell, which is closed at its downstream side; and an exhaust outflow cell, which is closed at its upstream side and is adjacent to the first cell with the partition wall positioned in between. The exhaust inflow cell is configured so that a NOx retention layer is formed on the inner surface thereof, and the exhaust outflow cell is configured so that a catalyst layer is formed on the inner surface thereof, respectively.
摘要:
Provided is an exhaust purification system for an internal combustion engine. The exhaust purification system comprising: a NOX purifying catalyst arranged in an exhaust passage of the internal combustion engine, wherein the NOX purifying catalyst comprises a base metal supported on a catalyst support; an oxygen sensor arranged at the downstream side of the NOX purifying catalyst in the exhaust passage; and an air-fuel, ratio control means for controlling the air-fuel ratio of exhaust gas flowing into the NOX purifying catalyst; wherein when the NOX purifying catalyst suffers from predetermined oxygen poisoning, the air-fuel ratio control means controls the air-fuel ratio of the exhaust gas, which flows into the NOX purifying catalyst, to a first air-fuel ratio wherein the first air-fuel ratio is richer than a theoretical air-fuel ratio, and then the air-fuel ratio control means switches the air-fuel ratio of the exhaust gas, which flows into the NOX purifying catalyst, to a second air-fuel ratio on the basis of an output value from the oxygen sensor wherein the second air-fuel ratio is leaner than the first air-fuel ratio.
摘要:
To provide a production method of a base metal catalyst for exhaust gas purification and with a catalyst activity, in which a base metal-supported catalyst is uniformly supported by a honeycomb substrate. A production method of a catalyst for exhaust gas purification, comprising the steps of preparing a honeycomb substrate having a plurality of cells, preparing a base metal-supported catalyst comprising a carrier supporting a metal containing a base metal having an exhaust gas purification performance, preparing a slurry having a pH of 7 or more by dispersing the base metal-supported catalyst in an aqueous solution, and introducing the slurry to a partition wall surface of the honeycomb substrate.
摘要:
To provide a production method of a base metal catalyst for exhaust gas purification and with a catalyst activity, in which a base metal-supported catalyst is uniformly supported by a honeycomb substrate. A production method of a catalyst for exhaust gas purification, comprising the steps of preparing a honeycomb substrate having a plurality of cells, preparing a base metal-supported catalyst comprising a carrier supporting a metal containing a base metal having an exhaust gas purification performance, preparing a slurry having a pH of 7 or more by dispersing the base metal-supported catalyst in an aqueous solution, and introducing the slurry to a partition wall surface of the honeycomb substrate.
摘要:
The invention relates to a catalyst able to exhibit an NOX purification performance at a low temperature and/or in an oxidizing atmosphere, that is, a nitrogen oxide purification catalyst including gold atoms and nickel atoms in a solid and a state of close proximity.