摘要:
An exhaust gas-purifying catalyst includes a support provided with one or more through-holes through which exhaust gas flows, and a catalytic layer supported by the support and containing an oxygen storage material. The exhaust gas-purifying catalyst includes a first section to which the exhaust gas is supplied, and a second section to which the exhaust gas having passed through the first section is supplied. The catalytic layer includes a layered structure of a first catalytic layer containing platinum and/or palladium and a second catalytic layer containing rhodium in the first catalytic section and further includes a third layer containing rhodium in the second section. The second section is smaller in oxygen storage material content per unit volumetric capacity than the first section.
摘要:
An exhaust gas-purifying catalyst includes a support provided with one or more through-holes through which exhaust gas flows, and a catalytic layer supported by the support and containing an oxygen storage material. The exhaust gas-purifying catalyst includes a first section to which the exhaust gas is supplied, and a second section to which the exhaust gas having passed through the first section is supplied. The catalytic layer includes a layered structure of a first catalytic layer containing platinum and/or palladium and a second catalytic layer containing rhodium in the first catalytic section and further includes a third layer containing rhodium in the second section. The second section is smaller in oxygen storage material content per unit volumetric capacity than the first section.
摘要:
The exhaust gas-purifying catalyst includes a substrate provided with one or more through-holes through which exhaust gas flows, and a catalyst layer which is supported by the substrate and contains precious metals and an oxygen storage material. The exhaust gas-purifying catalyst contains a first part to which the exhaust gas is supplied, and a second part to which the exhaust gas having passed through the first part is supplied and is smaller in the content of the oxygen storage material per unit volume than that of the first part.
摘要:
A catalyst for purification of exhaust gas, in which a noble metal is supported on a metal oxide support, has a basic site content of 1 mmol/L-cat or less, as determined on the basis of an amount of CO2 desorbed per liter of the catalyst as measured by a CO2 temperature-programmed desorption method.
摘要:
A catalyst for purification of exhaust gas, in which a noble metal is supported on a metal oxide support, has a basic site content of 1 mmol/L-cat or less, as determined on the basis of an amount of CO2 desorbed per liter of the catalyst as measured by a CO2 temperature-programmed desorption method.
摘要:
A particulate inorganic oxide containing aluminum oxide, a metal oxide forming no composite oxide with aluminum oxide, and an additional element including at least one of a rare-earth element and an alkali earth element, the inorganic oxide containing a secondary particle formed by aggregating primary particles; wherein at least a part of the secondary particle includes a plurality of first primary particles, each having a particle size of 100 nm or less, containing aluminum oxide and the additional element, and a plurality of second primary particles, each having a particle size of 100 nm or less, containing the metal oxide and the additional element; wherein at least a part of the first and second primary particles has a surface concentrated region where the additional element has a locally increased content in a surface layer part thereof.
摘要:
A particulate inorganic oxide containing aluminum oxide, a metal oxide forming no composite oxide with aluminum oxide, and an additional element including at least one of a rare-earth element and an alkali earth element, the inorganic oxide containing a secondary particle formed by aggregating primary particles; wherein at least a part of the secondary particle includes a plurality of first primary particles, each having a particle size of 100 nm or less, containing aluminum oxide and the additional element, and a plurality of second primary particles, each having a particle size of 100 nm or less, containing the metal oxide and the additional element; wherein at least a part of the first and second primary particles has a surface concentrated region where the additional element has a locally increased content in a surface layer part thereof.
摘要:
The catalyst carrier in accordance with the present invention is a catalyst carrier comprising a support containing an oxide and an element in group 3A of the periodic table, and a coating part covering at least a part of a surface of the support; wherein the coating part contains an element in group 3A of the periodic table; and wherein the element in group 3A contained in the coating part has a concentration higher than that of the element in group 3A contained in the support. In this case, even when a catalyst in which rhodium is supported by the catalyst carrier is used for a long time in a high temperature environment, the grain growth of rhodium particles can be suppressed, and the catalyst can fully be prevented from lowering its activity.
摘要:
The catalyst carrier in accordance with the present invention is a catalyst carrier comprising a support containing an oxide and an element in group 3A of the periodic table, and a coating part covering at least a part of a surface of the support; wherein the coating part contains an element in group 3A of the periodic table; and wherein the element in group 3A contained in the coating part has a concentration higher than that of the element in group 3A contained in the support. In this case, even when a catalyst in which rhodium is supported by the catalyst carrier is used for a long time in a high temperature environment, the grain growth of rhodium particles can be suppressed, and the catalyst can fully be prevented from lowering its activity.
摘要:
A composite oxide with a high oxygen storage capacity is provided without using cerium. The composite oxide is an iron oxide-zirconia composite oxide containing iron, zirconium, and a rare-earth element. The total content of Fe2O3, ZrO2, and an oxide of the rare-earth element is not less than 90 mass %, the content of an iron oxide in terms of Fe2O3 is 10 to 90 mass %, and the absolute value of the covariance COV(Fe, Zr+X) of the composite oxide, which has been baked in the atmosphere at a temperature of greater than or equal to 900° C. for 5 hours or more, is not greater than 20.