The present invention relates to a zeolite catalyst for preparing light alkene by dehydrogenation of light alkane including a cocatalyst metal selected from tin (Sn), germanium (Ge), lead (Pb), gallium (Ga) and indium (In), and a preparation method of the same. The catalyst of the present invention is prepared by using the zeolite having a relatively high pore diameter, a structure of at least 12-membered ring, and a low acidity due to a SiO.sub.2/Al.sub.2O.sub.3 ratio of at least 50, so that it can suppress the inactivation of a catalyst caused by pore clogging due to the formation of coke. Therefore the catalyst of the present invention can be effectively used as a catalyst for the preparation of light alkene by dehydrogenation of light alkane.

A continuous process for preparing exo-THDCPD by isomerization of endo-THDCPD includes the step of passing endo-THDCPD and hydrogen gas successively through a first reaction zone filled with a hydrogenation protectant and a second reaction zone filled with an isomerization catalyst to perform a hydroisomerization reaction so as to obtain exo-THDCPD, wherein the hydrogenation protectant is a supported metal hydrogenation catalyst, and the isomerization catalyst is a metal-modified molecular sieve catalyst. The process converts endo-THDCPD to exo-THDCPD, with a conversion of greater than 86% and a target product selectivity of greater than 94%.

Processes for selectively alkylating and/or dealkylating one ring of cyclohexylbenzyl and/or biphenyl compounds are provided. Such selective alkylation and/or dealkylation takes place through a transalkylation reaction between the cyclohexylbenzyl compound and a substituted or unsubstituted benzene, which replaces the phenyl moiety of the cyclohexylbenzyl compound. The transalkylated cyclohexylbenzyl may be dehydrogenated to give a corresponding biphenyl compound. The same reaction steps can be utilized with respect to biphenyl compounds by first partially hydrogenating one phenyl ring of the biphenyl compound, thereby obtaining a corresponding cyclohexylbenzyl compound, which may undergo the transalkylation and, optionally, subsequent dehydrogenation. Combinations of any two or more of partial hydrogenation, transalkylation, and dehydrogenation enable targeted substitution (or de-substitution) of only one ring of cyclohexylbenzyl and/or biphenyl compounds, thereby providing superior control in designing the synthesis of these compounds.

A method for producing diene comprises a step 1 of obtaining a straight chain internal olefin by removing a branched olefin from a raw material including at least the branched olefin and a straight chain olefin; and a step 2 of producing diene from the internal olefin by oxidative dehydrogenation using a first catalyst and a second catalyst, and the first catalyst has a complex oxide including bismuth, molybdenum and oxygen, and the second catalyst includes at least one selected from the group consisting of silica and alumina.

Processes for selectively alkylating and/or dealkylating one ring of cyclohexylbenzyl and/or biphenyl compounds are provided. Such selective alkylation and/or dealkylation takes place through a transalkylation reaction between the cyclohexylbenzyl compound and a substituted or unsubstituted benzene, which replaces the phenyl moiety of the cyclohexylbenzyl compound. The transalkylated cyclohexylbenzyl may be dehydrogenated to give a corresponding biphenyl compound. The same reaction steps can be utilized with respect to biphenyl compounds by first partially hydrogenating one phenyl ring of the biphenyl compound, thereby obtaining a corresponding cyclohexylbenzyl compound, which may undergo the transalkylation and, optionally, subsequent dehydrogenation. Combinations of any two or more of partial hydrogenation, transalkylation, and dehydrogenation enable targeted substitution (or de-substitution) of only one ring of cyclohexylbenzyl and/or biphenyl compounds, thereby providing superior control in designing the synthesis of these compounds.

A method for producing double-component modified molecular sieve comprises adding molecular sieve to an aqueous solution containing phosphorus to form a mixture, allowing the mixture to react at pH of 1-10, temperature of 70-200 C. and pressure of 0.2-1.2 MPa for 10-200 min, and then filtering, drying and baking the resultant to obtain phosphorus-modified molecular sieve, and then adding the phosphorus-modified molecular sieve to an aqueous solution containing silver ions, allowing the phosphorus-modified molecular sieve to react with silver ions at 0-100 C. in dark condition for 30-150 min, and then filtering, drying and baking. The obtained double-component modified molecular sieve contains 88-99 wt % molecular sieve with a ratio of silica to alumina between 15 and 60, 0.5-10 wt % phosphorus (based on oxides) and 0.01-2 wt % silver (based on oxides), all based on dry matter. A catalyst produced from the double-component modified molecular sieve has improved hydrothermal stability and microactivity.

In a process for producing methyl-substituted biphenyl compounds, a feed comprising at least one aromatic hydrocarbon selected from the group consisting of toluene, xylene and mixtures thereof is contacted with hydrogen in the presence of a hydroalkylation catalyst under conditions effective to produce a hydroalkylation reaction product comprising (methylcyclohexyl)toluenes and/or (dimethylcyclohexyl)xylenes. At least part of the hydroalkylation reaction product is then dehydrogenated in the presence of a dehydrogenation catalyst under conditions effective to produce a dehydrogenation reaction product comprising a mixture of methyl-substituted biphenyl compounds.

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.

Improved alkylation catalysts, alkylation methods, and methods of making alkylation catalysts are described. The alkylation method comprises reaction over a solid acid, zeolite-based catalyst and can be conducted for relatively long periods at steady state conditions. The alkylation catalyst comprises a crystalline zeolite structure, a Si/Al molar ratio of 20 or less, less than 0.5 weight percent alkali metals, and further having a characteristic catalyst life property. Some catalysts may contain rare earth elements in the range of 10 to 35 wt %. One method of making a catalyst includes a calcination step following exchange of the rare earth element(s) conducted at a temperature of at least 575 C. to stabilize the resulting structure followed by an deammoniation treatment. An improved method of deammoniation uses low temperature oxidation.

A continuous process for producing adamantane includes the steps of: 1) providing a liquid feed stream comprising endo-tetrahydrodicyclopentadiene; and 2) passing the liquid feed stream through a first reaction zone filled with a hydrogenation protective agent and a second reaction zone filled with an isomerization catalyst sequentially to carry out hydroisomerization reaction and obtain adamantane.