A catalyst for synthesizing aromatic hydrocarbons, a preparation method thereof and a method for synthesizing aromatic hydrocarbons by using the catalyst. The catalyst comprises acidic molecular sieve particles and zinc-aluminum composite oxide particles. The catalyst has relatively high selectivity to aromatic hydrocarbons, particularly BTX, stable performance, and a long single-pass life.

Catalysts and methods for use in conversion of glycerides and free fatty acids to biodiesel are described. A batch or continuous process may be used with the catalysts for transesterification of triglycerides with an alkyl alcohol to produce corresponding mono carboxylic acid esters and glycerol in high yields and purity. Similarly, alkyl and aryl carboxylic acids and free fatty acids are also converted to corresponding alkyl esters. Catalysts are capable of simultaneous esterification and transesterification under same process conditions. The described catalysts are thermostable, long lasting, and highly active.

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.

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 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.

Provided is a mordenite zeolite which can be produced without using an organic structure-directing agent, and has superior multivalent metal cation exchange capability. The mordenite zeolite according to the present invention containing silicon, a divalent metal M and aluminum in a skeletal structure, wherein the mordenite zeolite has the following atomic ratios in the state of Na-form. The mordenite zeolite preferably has a BET specific surface area of 250 m.sup.2/g or more and 500 m.sup.2/g or less and a micropore volume of 0.07 cc/g or more and 0.25 cc/g or less in the state of Na-form or H-form. Si/(M+Al)=5 or more and 10 or less, M/(M+Al)=0.1 or more and less than 1, and Na/(M+Al)=1 or more and less than 2.

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.

It is intended to provide a novel zeolite with a rare earth element-substituted framework which has a higher amount of NOx adsorbed and a method for producing the same, and a NOx adsorption member and a catalyst for automobile exhaust gas, etc. comprising the same. The present invention provides a zeolite with a rare earth element-substituted framework, comprising at least a zeolite and at least one rare earth element selected from the group consisting of Ce, La, Nd and Pr, wherein a content ratio of the rare earth element is 1 to 15% by mass in total based on the total amount, and one or some of Al and/or Si atoms constituting the framework of the zeolite are replaced with the rare earth element.

A catalyst for the carbonylation of dimethyl ether to methyl acetate. The catalyst comprises a zeolite, such as a mordenite zeolite, at least one Group IB metal, such as copper, and/or at least one Group VIII metal, such as iron, and at least one Group IIB metal, such as zinc. Such a catalyst with combined metals provides enhanced catalytic activity, improved stability, and improved selectivity to methyl acetate, and does not require a halogen promoter, as compared to a metal-free or copper only zeolite.