An improved NO.sub.x sensor with an NH.sub.3 oxidation catalyst. A sensor module may include a support component, a NO.sub.x sensing material positioned on the support component, and an NH.sub.3 oxidation catalyst. The NH.sub.3 oxidation catalyst may be layered on top of the NO.sub.x sensing material or the NH.sub.3 oxidation catalyst may be positioned upstream of the NO.sub.x sensing material such that the NH.sub.3 oxidation catalyst selectively converts NH.sub.3 to N.sub.2 while permitting NO.sub.x through to the NO.sub.x sensing material.

A method for processing an edge of a catalyst-supporting honeycomb structure in an exhaust gas denitration apparatus, in which an exhaust gas denitration apparatus equipped with a denitration catalyst-supporting honeycomb structure in which a corrugated plate-like inorganic fiber sheet and a flat plate-like inorganic fiber sheet, each supporting thereon a denitration catalyst containing a silica sol, titania particles, and ammonium metavanadate as a whole primary denitration catalyst layer, are alternately laminated, the edge of gas inlet side of the denitration catalyst-supporting honeycomb structure having the whole primary denitration catalyst layer is dipped in a denitration catalyst-containing slurry for edge processing composed of a silica sol, titania particles or kaolin particles, and ammonium metatungstate to form a coating layer of the denitration catalyst-containing slurry in the edge of the honeycomb structure, and this is dried and then calcinated to form an edge secondary denitration catalyst layer.

The presently claimed invention provides a layered three-way catalyst composition for purification of exhaust gases from internal combustion engines; said catalyst comprises a first layer comprising i) palladium supported on at least one alumina component and at least one oxygen storage component; and ii) barium oxide; wherein said first layer is essentially free of strontium, and a second layer comprising: i) rhodium supported on at least one zirconia component and/or alumina component; ii) strontium oxide and/or barium oxide; and iii) optionally, palladium supported on at least one alumina component. The presently claimed invention also provides a process for preparing the layered three-way catalyst composition which involves a technique such as incipient wetness impregnation technique(A); co-precipitation technique (B); or co-impregnation technique(C). The process includes preparing a first layer; preparing a second layer; and depositing the second layer on the first layer followed by calcination. The presently claimed invention further provides a a layered three-way catalytic article in which the three-way catalyst composition is deposited on a substrate in a layered fashion and its preparation.

A method for production of vanadium catalysts, including steps of 1) providing a mixture comprising a TiO.sub.2-based support and a composite oxide containing vanadium and antimony; 2) preparing a slurry containing the mixture obtained from step 1), and additive comprising at least one species selected from the group consisting of Si, Al, Zr, Ti, W and Mo, and a solvent; and 3) applying the slurry onto a substrate or processing the slurry into shaped bodies. The vanadium catalysts obtained/obtainable from the method, and use thereof for abatement of nitrogen oxides (NOx).

A structured monolithic catalyst has a structured monolithic carrier and a coating of active components. The coating of active components comprises active metal components and a substrate. The active metal components conclude a first metal element, a second metal element, a third metal element and a fourth metal element. The first metal element includes Fe and Co; the second metal element is at least one selected from the group consisting of the metal elements of the Group IA and/or IIA; the third metal element is at least one selected from the group consisting of the non-noble metal elements of the Groups IB to VIIB; and the fourth metal element is at least one selected from the group consisting of the noble metal elements.

Provided is an ammonia decomposition catalyst that exhibits high durability while maintaining high ammonia decomposition activity and low emissions of nitrogen oxides, for example, even under an atmosphere with a steam concentration of about 10% by volume. An ammonia decomposition catalyst capable of decomposing ammonia contained in an exhaust gas, the catalyst comprising an inorganic oxide loaded with an alloy containing Pt and Pd, and a zeolite.

The present invention relates to a catalyst comprising a carrier substrate of length L, coating A arranged as the first layer on the carrier and containing platinum on a metal oxide, and coating B applied as the second layer to coating A and containing a Cu-exchanged molecular sieve and no noble metal, wherein the total washcoat quantity of coating A is 40 g/l or more of washcoat in relation to the coated catalyst volume.

An exhaust gas purification filter comprises a base material part, a catalyst layer, and sealing parts. The base material part comprises porous partition walls. The catalyst layer is supported on pore walls of the partition walls. The partition walls supporting the catalyst layer comprise 10% or less of pores having a pore diameter of 50 μm or more. In the pore diameter distribution in the partition walls supporting the catalyst layer, the pore diameter D50 at which the cumulative pore volume becomes 50% is 10 μm or more. The pore diameter D50, and the pore diameter D10 at which the cumulative pore volume becomes 10%, satisfy the relationship of the following Expression 1.

(D50−D10)/D50≤0.9  Expression 1

The present invention relates to colloidal dispersions comprising a plurality of precious group nanoparticles, wherein about 90% or more of the precious group metal is in fully reduced form; a dispersion medium comprising a polar solvent; a water-soluble polymer suspension stabilizing agent; and a reducing agent, wherein the nanoparticle concentration is at least about 2 wt. % of the colloidal dispersion, wherein the nanoparticles have an average particle size of about 1 to about 6 nm and at least 95% of the nanoparticles have a particle size within this range; and further wherein the colloidal dispersion is substantially free of halides, alkali metals, alkaline earth metals and sulfur compounds. Methods of preparing, further processing, and using such colloidal dispersions are also provided herein.

A method of coating a substrate with a foam is described. The method comprises: (a) introducing a foam into a substrate comprising a plurality of channels through open ends of the channels at a first end of the substrate; and (b) applying at least one of (i) a vacuum to open ends of the channels at a second end of the substrate and (ii) a pressure to the open ends of the channels at the first end of the substrate; wherein the foam comprises a particulate material, and wherein the foam is particle stabilized.