This exhaust gas purifying catalyst is provided with a substrate and a catalyst layer formed on a surface of the substrate. The catalyst layer contains zeolite particles that support a metal, and a rare earth element-containing compound that contains a rare earth element. The rare earth element-containing compound is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite is 0.001 to 0.014 in terms of oxides.

Catalyst for oxygen storage capacity applications that include a zinc doped manganese-iron spinel mixed oxide material. The zinc doped manganese-iron spinel mixed oxide material may be synthesized by a co-precipitation method using a precipitation agent such as sodium carbonate and exhibits a high oxygen storage capacity.

Systems and methods for treating automotive vehicle emissions on board an automotive vehicle include the use of waste heat recovery, electrochemical water splitting, phototcatalytic water splitting, and selective catalytic reduction. Waste heat recovery is used to power electrochemical water splitting, or photocatalytic water splitting. Photons collected from a solar panel are used in photocatalytic water splitting, or in photo-assisted selective catalytic reduction. Hydrogen gas generated by water splitting is used in conjunction with catalytic reduction units to catalytically reduce NOx in an engine exhaust gas.

The present invention relates to a catalyst for the oxidation of NO, for the oxidation of ammonia, for the oxidation of HC and for the selective catalytic reduction of NOx, comprising a flow through substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the flow through substrate extending therethrough; a first coating comprising one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron; a second coating comprising a first platinum group metal component supported on a non-zeolitic first oxidic material and further comprising one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron; optionally a third coating comprising a second platinum group metal component supported on a second oxidic material; wherein the third coating is disposed on the surface of the internal walls and under the second coating over z % of the axial length of the substrate from the outlet end to the inlet end, with z being in the range of from 0 to 100; wherein the second coating extends over y % of the axial length of the substrate from the inlet end to the outlet end and is disposed either on the surface of the internal walls, or on the surface of the internal walls and the third coating, or on the third coating, with y being in the range of from 95 to 100; wherein the first coating extends over x % of the axial length of the substrate from the inlet end to the outlet end and is disposed on the second coating, with x being in the range of from 20 to y.

Provided is an exhaust gas purification device that ensures an improved purification performance and a suppressed pressure loss. An exhaust gas purification device of the present disclosure includes a honeycomb substrate and an inflow cell side catalyst layer. disposed on a surface on the inflow cell side in an inflow side region of the partition wall. When a gas permeability coefficient of an inflow side partition wall portion including the inflow side region of the partition wall and the inflow cell side catalyst layer is Ka and a gas permeability coefficient of an outflow side partition wall portion including an outflow side region at least from the predetermined position to an outflow side end of the partition wall is Kb, a ratio Ka/Kb of the gas permeability coefficients is within a range of 0.4 or more and 0.8 or less.

A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall is composed of a material containing cordierite as a main component thereof, porosity of the partition wall measured by a mercury press-in method is 60 to 68%, an average pore diameter of the partition wall measured by a mercury press-in method is 8 to 12 and in a pore diameter distribution which indicates a cumulative pore volume of the partition wall measured by a mercury press-in method, with a pore diameter (μm) on an abscissa axis and a log differential pore volume (cm.sup.3/g) on an ordinate axis, a first peak that includes a maximum value of the log differential pore volume has a pore diameter value of 10 μm or less, the pore diameter value corresponding to a ⅓ value width of the maximum value.

A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall is composed of a material containing cordierite as a main component thereof, porosity of the partition wall measured by a mercury press-in method is 60 to 68%, an average pore diameter of the partition wall measured by a mercury press-in method is 13 to 18 μm, and in a pore diameter distribution indicating a cumulative pore volume of the partition wall measured by a mercury press-in method, with a pore diameter (μm) on an abscissa axis and a log differential pore volume (cm.sup.3/g) on an ordinate axis, a first peak including a maximum value of the log differential pore volume has a pore diameter value of 15 μm or less, the pore diameter value corresponding to a ⅓ value width of the maximum value.

The present disclosure provides an exhaust gas purification catalyst having an improved low-temperature activity, which comprises a substrate and a catalyst coat layer formed on the substrate, wherein the catalyst coat layer contains Rh fine particles and a promoter comprising a Ce—Zr-based composite oxide and a Zr-based composite oxide not containing cerium oxide, wherein the Rh fine particles have an average particle size measured by a transmission electron microscope observation of 1.0 nm or more to 2.0 nm or less, and a standard deviation a of the particle size of 0.8 nm or less, and wherein the Rh fine particles are supported on each of the Ce—Zr-based composite oxide and the Zr-based composite oxide not containing cerium oxide.

An improved catalyst system is provided for the direct decomposition removal of NO.sub.x from an exhaust gas stream at temperatures between about 350° C. and about 600° C. that employs an (amorphous CuO.sub.x)/Co.sub.3O.sub.4 catalyst. The catalyst has an amorphous CuO.sub.x deposit on the surfaces of particles of Co.sub.3O.sub.4 spinel oxide. The catalyst is configured to reduce NO.sub.x to N.sub.2 without the presence of a reductant. The (amorphous CuO.sub.x)/Co.sub.3O.sub.4 catalyst is formed by the precipitation of the deposit from solution onto a suspension of Co.sub.3O.sub.4 spinel oxide particles. The catalyst system can be employed in a catalytic converter for the direct decomposition removal of NO.sub.x from an exhaust gas stream flowing at a temperature of less than or equal to about 500° C.

A copper-CHA zeolite catalyst for SCR of NO.sub.x is disclosed.