A method of manufacturing an exhaust gas-purifying catalyst comprising: moving a gas-flow control tool from a first position where the gas-flow control tool faces the first end face with the slurry in the reservoir interposed therebetween and is spaced apart from the slurry in the reservoir to a second position where the gas-flow control tool faces the first end face with a distance from the first end face shorter than that in the first position, in a period during which the slurry flows from the first end face's side toward the second end face's side, the gas-flow control tool being configured to generate a distribution of linear velocities of gas flows when the gas-flow control tool faces the first end face and gas is passed therethrough toward the first end face.

A nitrous oxide (N.sub.2O) removal catalyst composite is described, which includes: a N.sub.2O removal catalytic material on a carrier, wherein the catalytic material comprises a platinum group metal (PGM) component on a ceria-containing support having a single phase, cubic fluorite crystal structure. The catalytic material is effective to decompose nitrous oxide (N.sub.2O) to nitrogen (N.sub.2) and oxygen (O.sub.2) and/or to reduce N.sub.2O to N.sub.2 and water (H.sub.2O) and/or (CO.sub.2) under conditions of an exhaust stream of an internal combustion engine operating under conditions that are stoichiometric or lean with periodic rich transient excursions. Methods of making and using the same are also provided.

An oxidation catalyst is described for treating an exhaust gas produced by a diesel engine. The oxidation catalyst comprises a washcoat region disposed on a substrate, wherein the washcoat region comprises a mixture of: platinum (Pt) supported on a first support material; and ruthenium (Ru).

Catalyst material comprising a ternary spinel mixed oxide for treatment of an exhaust gas stream via direct decomposition removal of NOx to N.sub.2 and O.sub.2. The low temperature (from about 400 C. to about 650 C.), direct decomposition is accomplished without the need of a reductant molecule. In one example, Mn may be incorporated into metal oxide, such as Cu.sub.yCo.sub.3-yO.sub.4 spinel oxide, synthesized using co-precipitation techniques.

Described is a selective catalytic reduction material comprising a spherical particle including an agglomeration of crystals of a molecular sieve. The catalyst is a crystalline material that is effective to catalyze the selective catalytic reduction of nitrogen oxides in the presence of a reductant at temperatures between 200 C. and 600 C. A method for selectively reducing nitrogen oxides and an exhaust gas treatment system are also described.

Aspects of the present invention relate to a process for the preparation of a zeolitic material having a CHA-type framework structure comprising YO.sub.2 and X.sub.2O.sub.3, wherein said process comprises the steps of: (1) providing a mixture comprising one or more sources for YO.sub.2, one or more sources for X.sub.2O.sub.3, and one or more tetraalkylammonium cation R.sup.1R.sup.2R.sup.3R.sup.4N.sup.+-containing compounds as structure directing agent; (2) crystallizing the mixture obtained in step (1) for obtaining a zeolitic material having a CHA-type framework structure;
wherein Y is a tetravalent element and X is a trivalent element,
wherein R.sup.1, R.sup.2, and R.sup.3 independently from one another stand for alkyl,
wherein R.sup.4 stands for cycloalkyl, and
wherein the mixture provided in step (1) does not contain any substantial amount of a source for Z.sub.2O.sub.5, wherein Z is P, as well as to zeolitic materials which may be obtained according to the inventive process and to their use.

Provided are: a catalyst containing a carrier including SiO.sub.2 and Al.sub.2O.sub.3 and an iron element carried on the carrier, having a total amount of desorbed pyridine of 100 mol or more with respect to 1 g catalyst within the range of 150 C. inclusive to 450 C. exclusive in the TPD spectrum, and configured to promote the decomposition reaction of nitrogen monoxide and nitric monoxide; and a method of reducing nitrogen monoxide and nitric monoxide in a gas containing water and/or a sulfur oxide, nitrogen monoxide, and nitric monoxide, the method comprising bringing a gas and a reductant into contact with the catalyst to decompose nitrogen monoxide and nitric monoxide, the gas containing water and/or a sulfur oxide, nitrogen monoxide, and nitric monoxide.

The present disclosure relates to a process for preparing a catalyst for the selective catalytic reduction of nitrogen oxide. The process includes providing a zeolitic material comprising SiO.sub.2 and X.sub.2O.sub.3 in its framework structure, wherein X is a trivalent element; subjecting the zeolitic material to an ion exchange procedure with one or more copper (II) containing compounds; preparing a slurry comprising the Cu ion-exchanged zeolitic material, one or more iron (II) and/or iron (III) containing compounds, and a solvent system; providing a substrate and coating the slurry onto the substrate; and calcining the coated substrate. Furthermore, the present disclosure relates to a catalyst for the selective catalytic reduction of nitrogen oxide, an exhaust gas treatment system for the treatment of exhaust gas exiting from an internal combustion engine, and a method for the selective catalytic reduction of nitrogen oxides.

Methods and systems related to an exhaust gas treatment system including, in order: (i) a first means for injecting a nitrogenous reductant; (ii) a first selective catalytic reduction (SCR) catalyst; (iii) an ammonia slip catalyst (ASC); and (iv) a second selective catalytic reduction (SCR) catalyst,
wherein the ASC comprises an SCR catalyst and a supported palladium (Pd) component.

An object of the present invention is to increase the reduction performance of nitrogen oxides compared to existing three-way catalysts; simultaneously inhibit the emission of ammonia and nitrous oxide; simplify a process by means of a method of further doping an iridium-ruthenium catalyst into a commercial three-way catalyst; and expand the scope of application. The present invention provides a catalyst for simultaneously inhibiting the emission of ammonia and nitrous oxide by doping an iridium-ruthenium catalyst component into a three-way catalyst (TWC), a diesel oxidation catalyst, or a lean NOx trap supported on a honeycomb support.