Abstract: The present invention relates to a SCR catalytic article, comprising —a substrate and —a copper-containing small pore zeolite, having a crystal structure characterized by a decrease of unit cell volume upon sulfurization and desulfurization of less than ?3 as determined by an X-ray powder diffraction, wherein the sulfurization and desulfurization are carried out in accordance with the processes as described in the specification, and to an exhaust treatment system comprising the same. The present invention also relates to a method for determining whether a metal-promoted small pore zeolite is resistant to irreversible sulfur poisoning and a method for evaluating whether a metal-promoted small pore zeolite is qualified for resistance to irreversible sulfur poisoning.

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stability at high-reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica-to-alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Abstract: 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 SiO2 and X2O3 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.

Abstract: 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 including SiO2 and X2O3 in its framework structure, wherein X is a trivalent element; subjecting the zeolitic material to an ion exchange procedure with one or more iron (II) and/or iron (III) containing compounds; preparing a slurry including the Fe ion-exchanged zeolitic material, one or more copper (II) 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.

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Abstract: The present disclosure relates to copper-containing molecular sieve catalysts that are highly suitable for the treatment of exhaust containing NOx pollutants. The copper-containing molecular sieve catalysts contain ion-exchanged copper as Cu+2 and Cu(OH)+1, and DRIFT spectroscopy of the catalyst exhibits perturbed T-O-T vibrational peaks corresponding to the Cu+2 and Cu(OH)+1. In spectra taken of the catalytic materials, a ratio of the Cu+2 to the Cu(OH)+1 peak integration areas preferably can be ?1. The copper-containing molecular sieve catalysts are aging stable such that the peak integration area percentage of the Cu+2 peak (area Cu+2/(area Cu+2+area Cu(OH)+1)) increases by ?20% upon aging at 800° C. for 16 hours in the presence of 10% H2O/air, compared to the fresh state.

Abstract: The present disclosure provides a selective catalytic reduction (SCR) catalyst composition prepared from a first un-promoted zeolite having a first silica-to-alumina ratio (SAR) from about 5 to about 100, a promoter precursor, and a second un-promoted zeolite having a second silica-to-alumina ratio (SAR) from about 5 to about 100. The present disclosure further provides a method of forming the SCR catalyst composition, a catalytic article comprising the SCR catalyst composition, an engine exhaust gas treatment system comprising the SCR catalyst composition, and a method of removing nitrogen oxides from exhaust gas from a lean burn engine using the SCR catalyst composition.

Abstract: The present invention relates to a composition comprising a non-zeolitic oxidic material comprising alumina; an 8-membered ring pore zeolitic material comprising one or more of copper and iron, wherein the framework structure of the zeolitic material comprises a tetravalent element Y, a trivalent element X and oxygen, wherein the molar ratio of Y:X, calculated as YO2X2O3, is in the range of from 2: 1 to 40: 1; wherein at least part of the outer surface of the zeolitic material is covered by a layer comprising the non-zeolitic oxidic material; wherein Y comprises one or more of Si, Sn, Ti, Zr and Ge and X comprises one or more of Al, B, In and Ga.

Abstract: The present disclosure provides a method for preparing a selective catalytic reduction (SCR) catalyst, the SCR catalyst comprises a metal ion-exchanged zeolite. A method uses an in-situ ion exchange process. A process includes admixing a zeolite in the ammonium (NH4+) form with an aqueous mixture comprising water, a transition metal ion source, and, optionally, an acid, to form a slurry containing a metal ion-exchanged zeolite.

Abstract: A process for preparing a catalyst comprising a zeolitic material comprising copper, the process comprising (i) preparing an aqueous mixture comprising water, a zeolitic material comprising copper, a source of copper other than the zeolitic material comprising copper, and a non-zeolitic oxidic material selected from the group consisting of alumina, silica, titania, zirconia, ceria, a mixed oxide comprising one or more of Al, Si, Ti, Zr, and Ce and a mixture of two or more thereof; (ii) disposing the mixture obtained in (i) on the surface of the internal walls of a substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the substrate extending therethrough; and optionally drying the substrate comprising the mixture disposed thereon; (iii) calcining the substrate obtained in (ii).

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Abstract: Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Abstract: Described are exhaust gas treatment systems for treatment of a gasoline engine exhaust gas stream. The exhaust gas treatment systems comprise an ammonia generating catalyst and an ammonia selective catalytic reduction (SCR) catalyst downstream of the ammonia generating catalyst. The ammonia generating catalyst comprises a NOx storage component, a refractory metal oxide support, a platinum component, and a palladium component. The ammonia generating catalyst is substantially free of ceria. The platinum and palladium components are present in a platinum to palladium ratio of greater than about 1 to 1.

Abstract: Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings containing copper-containing molecular sieves disposed thereon, where for example a concentration of catalytic copper in an upstream zone is lower than the concentration of catalytic copper in a downstream zone.

Abstract: Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings disposed thereon, for example, a zoned coating comprising an upstream zone comprising a coating layer comprising a steam-activated iron-containing molecular sieve and a downstream zone comprising a coating layer comprising a high copper-containing molecular sieve.

Abstract: A lean gasoline exhaust treatment catalyst article is provided, the article comprising a catalytic material applied on a substrate, wherein the catalytic material comprises a first composition and a second composition, wherein the first and second compositions are present in a layered or zoned configuration, the first composition comprising palladium impregnated onto a porous refractory metal oxide material and rhodium impregnated onto a porous refractory metal oxide material; and the second composition comprising platinum impregnated onto a porous refractory metal oxide material. Methods of making and using such catalyst articles and the associated compositions and systems employing such catalyst articles are also described.

Abstract: A process for preparing a catalyst comprising a zeolitic material comprising copper, the process comprising (i) preparing an aqueous mixture comprising water, a zeolitic material comprising copper, a source of copper other than the zeolitic material comprising copper, and a non-zeolitic oxidic material selected from the group consisting of alumina, silica, titania, zirconia, ceria, a mixed oxide comprising one or more of Al, Si, Ti, Zr, and Ce and a mixture of two or more thereof; (ii) disposing the mixture obtained in (i) on the surface of the internal walls of a substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the substrate extending therethrough; and optionally drying the substrate comprising the mixture disposed thereon; (iii) calcining the substrate obtained in (ii).

Abstract: The present disclosure provides catalyst compositions for NOx conversion and catalytic articles incorporating such catalyst compositions. Certain catalyst compositions include a zeolite with a silica-to-alumina ratio from 5 to 20 and sufficient Cu exchanged into cation sites of the zeolite such that the zeolite has a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component in a concentration in the range of 1 to 20 wt. %, the copper trapping component including a plurality of particles having a particle size of about 0.5 to 20 microns. Certain catalyst compositions include, as the copper trapping component, alumina present as a plurality of alumina particles with a D90 particle size distribution in the range of 0.5 microns to 20 microns.

Abstract: The present disclosure relates to copper-containing molecular sieve catalysts that are highly suitable for the treatment of exhaust containing NOx pollutants. The copper-containing molecular sieve catalysts contain ion-exchanged copper as Cu+2 and Cu(OH)+1, and DRIFT spectroscopy of the catalyst exhibits perturbed T-O-T vibrational peaks corresponding to the Cu+2 and Cu(OH)+1. In spectra taken of the catalytic materials, a ratio of the Cu+2 to the Cu(OH)+1 peak integration areas preferably can be ?1. The copper-containing molecular sieve catalysts are aging stable such that the peak integration area percentage of the Cu+2 peak (area Cu+2/(area Cu+2+area Cu(OH)+1)) increases by ?20% upon aging at 800° C. for 16 hours in the presence of 10% H2O/air, compared to the fresh state.

Abstract: Described is a selective catalytic reduction catalyst comprising a zeolitic framework material of silicon and aluminum atoms, wherein a fraction of the silicon atoms are isomorphously substituted with a tetravalent metal. The catalyst can include a promoter metal such that the catalyst effectively promotes the reaction of ammonia with nitrogen oxides to form nitrogen and H2O selectively over a temperature range of 150 to 650° C. In another aspect, described is a selective catalytic reduction composite comprising an SCR catalyst material and an ammonia storage material comprising a transition metal having an oxidation state of IV. The SCR catalyst material promotes the reaction of ammonia with nitrogen oxides to form nitrogen and H2O selectively over a temperature range of 150° C. to 600° C., and the SCR catalyst material is effective to store ammonia at temperatures of 400° C. and above.