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 H.sub.2O 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 H.sub.2O 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. A method for selectively reducing nitrogen oxides, and a method for simultaneously selectively reducing nitrogen oxide and storing ammonia are also described. Additionally, an exhaust gas treatment system is also described.

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 H.sub.2O 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 H.sub.2O 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. A method for selectively reducing nitrogen oxides, and a method for simultaneously selectively reducing nitrogen oxide and storing ammonia are also described. Additionally, an exhaust gas treatment system is also described.

According to one or more embodiments, cationic polymers may be produced which include one or more monomers containing cations. Such cationic polymers may be utilized as structure directing agents to for mesoporous zeolites. The mesoporous zeolites may include micropores as well as mesopores, and may have a surface area of greater than 350 m.sup.2/g and a pore volume of greater than 0.3 cm.sup.3/g. Also described are core/shell zeolites, where at least the shell portion includes a mesoporous zeolite material.

According to one or more embodiments, cationic polymers may be produced which include one or more monomers containing cations. Such cationic polymers may be utilized as structure directing agents to for mesoporous zeolites. The mesoporous zeolites may include micropores as well as mesopores, and may have a surface area of greater than 350 m.sup.2/g and a pore volume of greater than 0.3 cm.sup.3/g. Also described are core/shell zeolites, where at least the shell portion includes a mesoporous zeolite material.

According to one or more embodiments, cationic polymers may be produced which include one or more monomers containing cations. Such cationic polymers may be utilized as structure directing agents to for mesoporous zeolites. The mesoporous zeolites may include micropores as well as mesopores, and may have a surface area of greater than 350 m.sup.2/g and a pore volume of greater than 0.3 cm.sup.3/g. Also described are core/shell zeolites, where at least the shell portion includes a mesoporous zeolite material.

According to one or more embodiments, cationic polymers may be produced which include one or more monomers containing cations. Such cationic polymers may be utilized as structure directing agents to for mesoporous zeolites. The mesoporous zeolites may include micropores as well as mesopores, and may have a surface area of greater than 350 m.sup.2/g and a pore volume of greater than 0.3 cm.sup.3/g. Also described are core/shell zeolites, where at least the shell portion includes a mesoporous zeolite material.

Provided is a beta zeolite also having exceptional catalytic activity as a catalyst other than an olefin epoxidation catalyst. This beta zeolite is synthesized without using an organic structure-directing agent and has titanium in the structural skeleton thereof, the Ti content being 0.10 mmol/g or higher. This beta zeolite preferably has an Si/Ti molar ratio of 20-200. Also, the Si/Al molar ratio is preferably 100 or higher.

A method for preparing titanium-containing molecular sieves include the following steps: irradiating a mixed solution containing a silicon source, a template and a titanium source by a light source containing ultraviolet light before crystallization, and then subjecting the mixed solution to crystallization and post-treatment to obtain the titanium-containing molecular sieve. In the method for preparing titanium-containing molecular sieve of the present invention, the mixed solution containing the silicon source, the template and the titanium source is treated with the ultraviolet light, and free radicals generated by the ultraviolet light can effectively dissociate titanium oligomers and accelerate the hydrolysis of the silicon source, and thus match the hydrolysis rate of a silicon-titanium precursor, thereby preventing a titanium monomer from self-polymerization to form non-framework titanium. Therefore, a titanium-containing molecular sieve that does not contain the non-framework titanium can be quickly prepared.

The present invention relates to an SCR-active material, comprising a small-pore zeolite, aluminum oxide and copper, characterized in that it contains 5 to 25 wt-% of aluminum oxide in relation to the entire material and that the copper is present on the aluminum oxide in a first concentration and on the small-pore zeolite in a second concentration.

The present invention relates to an SCR-active material, comprising a small-pore zeolite, aluminum oxide and copper, characterized in that it contains 5 to 25 wt-% of aluminum oxide in relation to the entire material and that the copper is present on the aluminum oxide in a first concentration and on the small-pore zeolite in a second concentration.