A catalyst with a porous, ceramic support body having a porosity which is formed by pores in at least a part of the ceramic support body, and which furthermore has a catalytically active washcoat coating applied to the ceramic support body, which catalytically active washcoat coating having a layer thickness, comprises a permanent catalytically inactive impregnation comprising at least one catalytically inactive inorganic component, and wherein the permanent inactive impregnation has a layer thickness and is present at least partially between a surface of the porous ceramic support body and the catalytically active washcoat coating is present in the pores of the ceramic support body in a region with reduced porosity underneath the surface of the ceramic support body.

Method of preparing monolithic SCR catalyst with a plurality of gas flow channels comprising the steps of (a) providing a monolithic shaped substrate with a plurality of parallel gas flow channels; (b) coating the substrate with a wash coat slurry comprising vanadium oxide precursor compounds and titania and optionally tungsten oxide precursor compounds; and (c) drying the thus coated substrate with a drying rate of 5 mm/min or less along flow direction through the gas flow channels; and (d) activating the dried coated substrate by calcining.

The purpose of the present invention is to provide an exhaust purifier (1) which is capable of restoring a pressure difference (P) and a purification rate (NOx removal efficiency) of a NOx catalyst (14) to the initial states thereof. An exhaust purifier (1) for removing particulate matter adhered to a NOx catalyst (14) by injecting pressurized air using an air injection nozzle (16) into a housing (13) of a catalyst reactor (12) in which the NOx catalyst (14) serving as a catalyst is positioned, wherein the particulate matter is removed by increasing the pressure inside the catalyst reactor (12) to a prescribed pressure (IP) within a prescribed interval of time (t) by operating an injection valve (17) for supplying pressurized air.

A honeycomb filter includes a plugged honeycomb structure body which has cell rows arranged along one direction in a cross section of the honeycomb structure body and including a first cell row constituted of inflow cells and a second cell row including outflow cells. A width P1 (mm) of the first cell row, a width P2 (mm) of the second cell row and a curvature radius R (m) of a curved shape of corner portions of a polygonal shape of each cell satisfy relations of Equations (1) and (2) below: Equation (1): 2100(P1/P2100)50, and Equation (2): 0.4(R/1000)/((P1+P2)/2)10020.

A processing apparatus equipped with a catalyst-supporting honeycomb structure, which is characterized in that corrugated plate-like glass fiber papers having a functional catalyst supported thereon and flat plate-like glass fiber papers having the same functional catalyst supported thereon are alternately laminated without being bonded to each other, to form a catalyst-supporting honeycomb structure, and this catalyst-supporting honeycomb structure is packed in a casing.

Method of preparing a monolithic SCR catalyst with a plurality of gas flow channels comprising the steps of (a) providing a monolithic shaped substrate with a plurality of parallel gas flow channels; (b) coating the substrate with a washcoat slurry comprising titania; (c) drying and calcining the washcoat slurry; (d) impregnating the dried and calcined washcoat with an 10 aqueous impregnation solution comprising a precursor of a vanadium oxide; (e) drying the thus coated and impregnated washcoat at a drying rate of 5 mm/min or less along flow direction through the gas flow channels; and 15 (f) activating the dried, coated and impregnated washcoat by calcining.

An exhaust system for treating an exhaust gas from an internal combustion engine is disclosed. The system comprises a modified lean NO.sub.x trap (LNT), a urea injection system, and an ammonia-selective catalytic reduction (NH.sub.3-SCR) catalyst. The modified LNT comprises platinum, palladium, barium, and a ceria-containing material, and has a platinum:palladium molar ratio of at least 3:1. The modified LNT stores NO.sub.x at temperatures below about 200? C. and releases the stored NO.sub.x at temperatures above about 200? C. The urea injection system injects urea at temperatures above about 180? C.

An exhaust aftertreatment system configured to reduce nitrous oxide (N.sub.2O) formation includes a first selective catalytic reduction (SCR) catalyst. The first SCR catalyst is configured for low N.sub.2O formation and low ammonia (NH.sub.3) storage capacity. A second SCR catalyst is positioned downstream of the first SCR catalyst. The second SCR catalyst is configured for high NH.sub.3 storage capacity.

A catalyst composition comprisinga support comprising TiO.sub.2,a composite oxide containing vanadium and antimony, which has a rutile-type structure different from VSbO .sub.4 and V.sub.0.92Sb.sub.0.92O.sub.4 as determined by X-ray diffraction (XRD) analysis with CuK? radiation, andoptionally, one or more selected from the group consisting of oxides of silicon, oxides of vanadium and oxides of antimony, for selective catalytic reduction of nitrogen oxides; to a process for preparing the catalyst composition, to the catalyst composition obtained/obtainable by the process and to use of the same for selective catalytic reduction of nitrogen oxides.

Ceramic candle filter and use of the filter in the removal of particulate matter in form of soot, ash, metals and metal compounds, together with hydrocarbons and nitrogen oxides being present in process off-gas or engine exhaust gas, the filter comprises a combined SCR and oxidation catalyst arranged at least on the dispersion side and/or within wall of the filter, the combined SCR and oxidation catalyst comprises palladium, a vanadium oxide and titania.