In relation to a Cu-based delafossite-type oxide that is effective as an exhaust gas purification catalyst, Cu is placed in a high catalytic activity low-valence state, whereby a novel Cu-based delafossite-type oxide having higher activity than in the past is provided. Proposed is a delafossite-type oxide for an exhaust gas purification catalyst that is represented by a general formula ABO.sub.2, wherein Cu and Ag are contained in the A site of the general formula, one or two or more elements selected from the group consisting of Mn, Al, Cr, Ga, Fe, Co, Ni, In, La, Nd, Sm, Eu, Y, V, and Ti are contained in the B site of the general formula, and Ag is contained at a ratio of 0.001 at. % or more and less than 20 at. % in the A site of the general formula.

Sulfur-resistant synergized platinum group metals (SPGM) catalysts with significant oxidation capabilities are disclosed. Catalytic layers of SPGM catalyst samples are prepared using conventional synthesis techniques to build a washcoat layer completely or substantially free of PGM material. The SPGM catalyst includes a washcoat layer comprising YMn.sub.2O.sub.5 (pseudobrookite) and an overcoat layer including a Pt/Pd composition with total PGM loading of at or below 5.0 g/ft.sup.3. Resistance to sulfur poisoning and catalytic stability is observed under 5.2 gS/L condition to assess significant improvements in NO oxidation, and HC and CO conversions.

Provided is a method of manufacturing a nano-catalyst filter, which includes depositing through electrodeposition a catalyst precursor inside a porous filter to which an electrode layer is attached. Using this method, a nano-catalyst can be uniformly deposited inside a porous ceramic filter, and high catalyst efficiency can be obtained only using a small amount of the nano-catalyst.

Provided are: a complex oxide that exhibits high redox ability even at low temperatures, has excellent heat resistance, and stably retains these characteristics even on repeated oxidation and reduction at high temperature; a method for producing the same; and an exhaust gas purification catalyst. The inventive complex oxide contains more than 0 but no more than 20 parts by mass of Si, calculated as SiO.sub.2, per total 100 parts by mass of rare earth metal elements including Ce, calculated as oxides; and has a characteristic such that when it is subjected to temperature-programmed reduction (TPR) measurement in a 10% hydrogen-90% argon atmosphere at from 50° C. to 900° C. with the temperature increasing at a rate of 10° C./min, followed by oxidation treatment at 500° C. for 0.5 hours, and then temperature-programmed reduction measurement is performed again, its calculated reduction rate at and below 400° C. is at least 1.5%.

Disclosed herein is a system for the removal of volatile organic compounds, carbon monoxide and nitrogen oxides from off-gas even at high NO.sub.2 to NO.sub.x ratios, wherein the amount of NO.sub.2 within NO.sub.x is higher than or equal to 50 mol-%, comprising a source of ammonia, means for introducing ammonia into a catalytic article having an SCR functionality; a catalytic article having both an oxidation and an SCR functionality, the catalytic article comprising a catalyst substrate and a catalyst composition comprising at least one platinum group metal and/or at least one platinum group metal oxide, at least one oxide of titanium and at least one oxide of vanadium, wherein the washcoat is located in and/or on the walls of the catalyst substrate: means for measuring the amount of NO.sub.x and/or the ammonia slip between the outlet end of the catalytic article and the stack or at the stack, at least one carbon monoxide source, and means for introducing carbon monoxide into the catalytic article. Optionally, an SCR catalytic article can be placed upstream of downstream of the cata-lytic article having both an oxidation and an SCR functionality. Also disclosed is a method for the removal of volatile organic compounds, carbon monoxide and nitrogen oxides from off-gas introducing carbon monoxide in order to keep the amount of NOx and/or the ammonia slip between the outlet end of the catalytic article and the stack or at the stack at predetermined values. The method makes use of the system according to the invention. The system and the method can be used for the cleaning of flue gas.

An after treatment system for a lean-burn engine is disclosed. The after treatment system is sequentially equipped with an ammonia production catalyst module, a selective catalytic reduction (SCR) catalyst, and a CO clean-up catalyst (CUC) on an exhaust pipe through which an exhaust gas flows and which is connected to a lean-burn engine. An exhaust flow changer is disposed between the ammonia production catalyst module and the SCR catalyst. The exhaust flow changer changes flow of an exhaust gas discharged from the ammonia production catalyst module according to a temperature of the SCR catalyst.

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.

The present invention relates to catalyst compositions containing a mixed oxide catalyst of formula (I) or formula (II) as described herein, their preparation, and their use in a process for ammoxidation of various organic compounds to their corresponding nitriles and to the selective catalytic oxidation of excess NH.sub.3 present in effluent gas streams to N.sub.2 and/or NO.sub.x.

The present disclosure features a high metal cation content zeolite-based binary catalyst (e.g., a high copper and/or iron content zeolite-based binary catalyst, where the zeolite can be a chabazite) for NO.sub.x reduction, having relatively low N.sub.2O make, and having low corresponding metal oxide content; where the metal in the metal oxide corresponds to the metal of the metal cation. The present disclosure also describes the synthesis of the zeolite-based binary catalyst having high metal cation content.

An assembly for use in treating gaseous exhaust emissions has an inductive heater mounted next to a gaseous emissions treatment unit. and downstream substrate units or upstream and downstream sections of a single substrate. The upstream unit or section has linear passages extending the length of the first substrate body for the passage of emissions gas but with some of the passages blocked by metal inserts for use in inductive heating of the upstream unit. The concentration of metal inserts is high and the metal inserts are distributed to enable rapid intense inductive heating of the slice or section to achieve light off temperature rapidly in order to pass heat-supplemented gaseous emissions at light-off temperature to the downstream substrate or section as quickly as possible.