Provided is a composition comprising a ceria-zirconia mixed oxide, the ceria-zirconia mixed oxide being surface-modified with a perovskite type compound of formula (I); wherein formula (I) is defined by A.sub.x-yA.sub.yB.sub.1-zB.sub.zO.sub.3; where: A is an ion of a metal selected from the group consisting of Li, Na, K, Cs, Mg, Sr, Ba, Ca, Y, La, Ce, Pr, Nd, and Gd; A is an ion of a metal selected from the group consisting of Li, Na, K, Cs, Mg, Sr, Ba, Ca, Y, La, Ce, Pr, Nd, and Gd; B is an ion of a metal selected from the group consisting of Cu, Mn, Mo, Co, Fe, Ni, Cr, Ti, Zr, Al, Ga, Sc, Nb, V, W, Bi, Zn, Sn, Pt, Rh, Pd, Ru, Au, Ag, and Ir; B is an ion of a metal selected from the group consisting of Cu, Mn, Mo, Co, Fe, Ni, Cr, Ti, Zr, Al, Ga, Sc, Nb, V, W, Bi, Zn, Sn, Pt, Rh, Pd, Ru, Au, Ag, and Ir; x is from 0.7 to 1; y is from 0 to 0.5; and z is from 0 to 0.5.

A catalyst composition comprising an intermetallic compound is disclosed. The intermetallic compound comprises a transition metal selected from Fe, Ce, Y, Nb and combinations thereof; and a noble metal selected from Pt, Pd, Rh and combinations thereof. The invention further relates to a washcoat comprising the catalyst composition, and a catalyst article comprising the catalyst composition, a method of treating exhaust gas with the catalyst article, a method for manufacturing the catalyst article and systems comprising the catalyst article.

A method of manufacturing a catalyst article, the method comprising: providing a complex of a compound of formula (I):

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and a PGM, R1 is H or C.sub.1-C.sub.6 alkyl, R2 is H, OH, or OC.sub.1-C.sub.4 alkyl, the PGM comprising palladium; providing a support material; applying the complex to the support material to form a loaded support material; disposing the loaded support material on a substrate; and heating the loaded support material to form nanoparticles of the PGM on the support material.

A ceria-zirconia-based composite oxide oxygen storage material with a fast oxygen storage rate having an OSC ability enabling fast response to changes in exhaust gas which does not greatly fluctuate in composition, but varies at a fast rate near the stoichiometric air-fuel ratio, an exhaust gas purification catalyst, and a honeycomb structure for exhaust gas purification are provided.

A ceria-zirconia-based composite oxide oxygen storage material, which oxygen storage material has a molar ratio of cerium and zirconium, by cerium/(cerium+zirconium), of 0.33 to 0.90, has an ion conductivity measured by an AC impedance method of 110.sup.5 S/cm or more at 400 C., and contains metal ions M of one or more types of rare earth elements selected from Sm.sup.3+, Eu.sup.3+, Pr.sup.3+, Gd.sup.3+, and Dy.sup.+3 with a coordination number of over 7.0 in an amount of 0.5 mol % to 15 mol % with respect to the total amount of cations.

The exhaust gas purification device is provided with a wall flow structure substrate that has an entry-side cell, an exit-side cell and a porous partition, first catalyst parts which are formed in small pores having a relatively small pore diameter among internal pores in the partition, and second catalyst parts which are formed in large pores having a relatively large pore diameter among the internal pores in the partition. The first catalyst parts and the second catalyst parts each contain a carrier and at least one type of noble metal from among Pt, Pd and Rh supported on the carrier. The noble metal content in the first catalyst parts is smaller than the noble metal content in the second catalyst parts per 1 liter of substrate volume.

This disclosure is intended to suppress a noble metal supported by a three-way catalyst from being deteriorated by oxidation with the execution of fuel cut processing in a suitable manner. A control apparatus for a naturally aspirated gasoline engine is provided with a three-way catalyst, a first throttle valve, a second throttle valve arranged in the intake passage at the downstream side of the first throttle valve, an EGR valve, and a controller. When the controller carries out fuel cut processing and the temperature of the three-way catalyst is equal to or higher than a predetermined temperature, the controller introduces the EGR gas into a cylinder of the gasoline engine as intake air by fully closing the first throttle valve and by opening the EGR valve, and further controls an amount of the EGR gas by adjusting the degree of opening of the second throttle valve.

A three-way catalyst article, and its use in an exhaust system for internal combustion engines, is disclosed. In particular, provided is a catalyst article for treating exhaust gas comprising: a substrate comprising an inlet end and an outlet end with an axial length L; and a first catalytic region on the substrate; wherein the first catalytic region comprises a first PGM component and a first alumina, wherein the first alumina is doped with from 0.01 to less than 5.0 wt. % Ta, based on the total weight of the doped alumina.

Provided is a method of manufacturing an alkaline-earth-metal-sulfate-loaded support material, the method comprising: providing a first slurry comprising a support material, alkaline-earth-metal ions and an organic compound, wherein the organic compound comprises a functional group selected from a sulfo group (SO.sub.3H), a sulfonyl group (S(?O).sub.2) and a sulfinyl group (S(?O)); spray drying the first slurry to provide a spray-dried powder; and heating the spray-dried powder to form an alkaline-earth-metal-sulfate-loaded support material.

An exhaust purification system includes an LAF sensor provided in an exhaust pipe and generates a signal corresponding to an air-fuel ratio of exhaust gas. An upstream catalytic converter is downstream of the LAF sensor and has a catalyst to purify the exhaust gas. An O2 sensor is downstream of the upstream catalytic converter, and generates a signal corresponding to the air-fuel ratio of the exhaust gas. A GPF is downstream of a the O2 sensor and purifies the exhaust gas. An ECU controls an air-fuel mixture in an engine using output signal KACT of the LAF sensor and an output signal VO2 of the O2 sensor such that the air-fuel ratio of exhaust gas flowing into the GPF converges to a target value near the stoichiometric ratio. The GPF has a filter substrate and a downstream TWC supported by a partition of the filter substrate.

An oxidation catalyst composite, methods and systems for the treatment of exhaust gas emissions from an advanced combustion engine, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO) and the reduction of nitrogen oxides (NOx) from a diesel engine and an advanced combustion diesel engine are disclosed. More particularly, washcoat compositions are disclosed comprising at least two washcoat layers, a first washcoat comprising a palladium component and a first support containing cerium and a second washcoat containing platinum and one or more molecular sieves.