A method of converting nitrogen oxides in a gas to nitrogen by contacting the nitrogen oxides with a nitrogenous reducing agent in the presence of a zeolite catalyst containing at least one transition metal, wherein the zeolite is a small pore zeolite containing a maximum ring size of eight tetrahedral atoms, wherein the at least one transition metal is selected from the group consisting of Cr, Mn, Fe, Co, Ce, Ni, Cu, Zn, Ga, Mo, Ru, Rh, Pd, Ag, In, Sn, Re, Jr and Pt.

A de-hydrogenation catalyst and its use in dehydrogenation of hydrocarbons. The catalyst has low cracking activity and comprises gallium or gallium and platinum on an essentially non-acidic and amorphous alumina-phosphate or silica-alumina-phosphate support with an empirical chemical composition of [Al2O3][SiO2].sub.Y[P2O5].sub.Z, wherein Y is between 0 and 0.2 and Z is between 0.01 and 1.1, with a BET surface area above 50 m.sup.2/g, as measured by N2 adsorption experiment.

The present invention relates to catalyst comprising one or more metal oxides and/or metalloid oxides and a zeolitic material having the CHA framework structure comprising YO.sub.2 and X.sub.2O.sub.3, wherein Y is a tetravalent element and X is a trivalent element, wherein the zeolitic material comprises one or more alkaline earth metals selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof, and wherein the framework of the zeolitic material comprised in the catalyst contains substantially no phosphorous, as well as to a process for the preparation of a catalyst comprising one or more alkaline earth metals selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof and to a catalyst obtainable therefrom. Furthermore, the present invention relates to a method for the conversion of oxygenates to olefins employing the inventive catalyst, as well as to the use of the inventive catalyst in specific applications.

The present invention relates to catalyst comprising one or more metal oxides and/or metalloid oxides and a zeolitic material having the CHA framework structure comprising YO.sub.2 and X.sub.2O.sub.3, wherein Y is a tetravalent element and X is a trivalent element, wherein the zeolitic material comprises one or more alkaline earth metals selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof, and wherein the framework of the zeolitic material comprised in the catalyst contains substantially no phosphorous, as well as to a process for the preparation of a catalyst comprising one or more alkaline earth metals selected from the group consisting of Mg, Ca, Sr, Ba, and combinations of two or more thereof and to a catalyst obtainable therefrom. Furthermore, the present invention relates to a method for the conversion of oxygenates to olefins employing the inventive catalyst, as well as to the use of the inventive catalyst in specific applications.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an LTL Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.

A passive NO.sub.x adsorber is disclosed. The passive NO.sub.x adsorber is effective to adsorb NO.sub.x at or below a low temperature and release the adsorbed NO.sub.x at temperatures above the low temperature. The passive NO.sub.x adsorber comprises a noble metal and a molecular sieve having an LTL Framework Type. The invention also includes an exhaust system comprising the passive NO.sub.x adsorber, and a method for treating exhaust gas from an internal combustion engine utilizing the passive NO.sub.x adsorber.

A molecular sieve has a silica/alumina molar ratio of 100-300, and has a mesopore structure. One closed hysteresis loop appears in the range of P/P.sub.0=0.4-0.99 in the low temperature nitrogen gas adsorption-desorption curve, and the starting location of the closed hysteresis loop is in the range of P/P.sub.0=0.4-0.7. The catalyst formed from the molecular sieve as a solid acid not only has a good capacity of isomerization to reduce the freezing point, but also can produce a high yield of the product with a lower pour point. The process for preparing the catalyst involves steps including crystallization, filtration, calcination, and hydrothermal treatment.

A molecular sieve has a silica/alumina molar ratio of 100-300, and has a mesopore structure. One closed hysteresis loop appears in the range of P/P.sub.0=0.4-0.99 in the low temperature nitrogen gas adsorption-desorption curve, and the starting location of the closed hysteresis loop is in the range of P/P.sub.0=0.4-0.7. The catalyst formed from the molecular sieve as a solid acid not only has a good capacity of isomerization to reduce the freezing point, but also can produce a high yield of the product with a lower pour point. The process for preparing the catalyst involves steps including crystallization, filtration, calcination, and hydrothermal treatment.

A method of converting nitrogen oxides in a gas to nitrogen by contacting the nitrogen oxides with a nitrogenous reducing agent in the presence of a zeolite catalyst containing at least one transition metal, wherein the zeolite is a small pore zeolite containing a maximum ring size of eight tetrahedral atoms, wherein the at least one transition metal is selected from the group consisting of Cr, Mn, Fe, Co, Ce, Ni, Cu, Zn, Ga, Mo, Ru, Rh, Pd, Ag, In, Sn, Re, Ir and Pt.

A new family of crystalline microporous metalloalumino(gallo)phosphosilicate molecular sieves has been synthesized and are designated high charge density (HCD) MeAPSOs. These metalloalumino(gallo)phosphosilicate are represented by the empirical formula of:

R.sup.p+.sub.rA.sup.+.sub.mM.sup.2+.sub.wE.sub.xPSi.sub.yO.sub.z

where A is an alkali metal such as potassium, R is at least one quaternary ammonium cation such as ethyltrimethylammonium, M is a divalent metal such as Zn and E is a trivalent framework element such as aluminum or gallium. This family of metalloalumino(gallo)phosphosilicate materials are stabilized by combinations of alkali and quaternary ammonium cations, enabling unique, high charge density compositions. The HCD MeAPSO family of materials have catalytic properties for carrying out various hydrocarbon conversion processes and separation properties for separating at least one component.