An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, described is an oxidation catalyst composite including a first oxidation component comprising a first refractory metal oxide support, palladium (Pd) and platinum (Pt); a NO.sub.x storage component comprising one or more of alumina, silica, titania, ceria, or manganese; and a second oxidation component comprising a second refractory metal oxide, a zeolite, and Pt. The oxidation catalyst composite is sulfur tolerant, adsorbs NOx and thermally releases the stored NO.sub.x at temperature less than 350 C.

The present invention provides a novel process and system in which a mixture of carbon monoxide and hydrogen synthesis gas, or syngas, is converted into hydrocarbon mixtures composed of high quality gasoline components, aromatic compounds, and lower molecular weight gaseous olefins in one reactor or step. The invention utilizes a novel molybdenum-zeolite catalyst in high pressure hydrogen for conversion, as well as a novel rhenium-zeolite catalyst in place of the molybdenum-zeolite catalyst, and provides for use of the novel catalysts in the process and system of the invention.

A catalyst containing LF-type B acid preparing ethylene using direct conversion of syngas is a composite catalyst and formed by compounding component A and component B in a mechanical mixing mode. The active ingredient of the component A is a metal oxide; the component B is a zeolite of MOR topology; and a weight ratio of the active ingredients in the component A to the component B is 0.1-20. The reaction process has an extremely high product yield and selectivity, with the selectivity for light olefin reaching 80-90%, wherein ethylene has high space time yield and can reach selectivity of 75-80%. Meanwhile, the selectivity for a methane side product is extremely low (<15%).

A catalyst containing LF-type B acid preparing ethylene using direct conversion of syngas is a composite catalyst and formed by compounding component A and component B in a mechanical mixing mode. The active ingredient of the component A is a metal oxide; the component B is a zeolite of MOR topology; and a weight ratio of the active ingredients in the component A to the component B is 0.1-20. The reaction process has an extremely high product yield and selectivity, with the selectivity for light olefin reaching 80-90%, wherein ethylene has high space time yield and can reach selectivity of 75-80%. Meanwhile, the selectivity for a methane side product is extremely low (<15%).

An organic base modified composite catalyst for producing ethylene by hydrogenation of carbon monoxide is a composite catalyst and formed by compounding component I and component II in a mechanical mixing mode. The active ingredient of the component I is a metal oxide; the component II is an organic base modified zeolite of MOR topology; and a weight ratio of the active ingredients in the component I to the component II is 0.1-20, and preferably 0.3-8. The reaction process has an extremely high product yield and selectivity. The selectivity of C.sub.2-C.sub.3 olefins is as high as 78-87%; the selectivity of hydrocarbon products with more than 4 C atoms is less than 10%; the selectivity of a methane side product is extremely low (<9%); and meanwhile, the selectivity of the ethylene is 75-82%.

An organic base modified composite catalyst for producing ethylene by hydrogenation of carbon monoxide is a composite catalyst and formed by compounding component I and component II in a mechanical mixing mode. The active ingredient of the component I is a metal oxide; the component II is an organic base modified zeolite of MOR topology; and a weight ratio of the active ingredients in the component I to the component II is 0.1-20, and preferably 0.3-8. The reaction process has an extremely high product yield and selectivity. The selectivity of C.sub.2-C.sub.3 olefins is as high as 78-87%; the selectivity of hydrocarbon products with more than 4 C atoms is less than 10%; the selectivity of a methane side product is extremely low (<9%); and meanwhile, the selectivity of the ethylene is 75-82%.

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, described is an oxidation catalyst composite including a first oxidation component comprising a first refractory metal oxide support, palladium (Pd) and platinum (Pt); a NO.sub.x storage component comprising one or more of alumina, silica, titania, ceria, or manganese; and a second oxidation component comprising a second refractory metal oxide, a zeolite, and Pt. The oxidation catalyst composite is sulfur tolerant, adsorbs NO.sub.x and thermally releases the stored NO.sub.x at temperature less than 350 C.

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, described is an oxidation catalyst composite including a first oxidation component comprising a first refractory metal oxide support, palladium (Pd) and platinum (Pt); a NO.sub.x storage component comprising one or more of alumina, silica, titania, ceria, or manganese; and a second oxidation component comprising a second refractory metal oxide, a zeolite, and Pt. The oxidation catalyst composite is sulfur tolerant, adsorbs NO.sub.x and thermally releases the stored NO.sub.x at temperature less than 350 C.

Disclosed herein is a process for producing para-xylene comprising the steps of: (a) contacting a feedstock comprising toluene with a first catalyst under effective vapor phase toluene disproportionation conditions to disproportionate said toluene and produce a first product comprising benzene, unreacted toluene and greater than equilibrium amounts of para-xylene; and (b) contacting a feedstock comprising C.sub.9+ aromatic hydrocarbons and benzene with a second catalyst in the presence of 0 wt. % or more of hydrogen having a 0 to 10 hydrogen/hydrocarbon molar ratio under effective C.sub.9+ transalkylation conditions to transalkylate said C.sub.9+ aromatic hydrocarbons and produce a second product comprising xylenes.

A method for producing an oligosilane which includes a reaction step of producing an oligosilane by dehydrogenative coupling of hydrosilane. The reaction step is carried out in the presence of a catalyst containing at least one transition element selected from the group consisting of Periodic Table group 3 transition elements, group 4 transition elements, group 5 transition elements, group 6 transition elements, and group 7 transition elements. Also disclosed is a method for producing a catalyst for dehydrogenative coupling that produces an oligosilane by dehydrogenative coupling of hydrosilane.