Paraffin isomerization catalyst comprising of from 0.01 to 5 wt. % of a Group VIII noble metal on a carrier containing alumina and zeolite beta having a silica to alumina molar ratio (SAR) of from 5 to 15 and process employing such catalyst for isomerization of a hydrocarbon feed containing paraffins having of from 4 to 8 carbon atoms.

The present invention provides a modified composite molecular sieve, and a preparation method and an application of the modified composite molecular sieve. The modified composite molecular sieve comprises SiO.sub.2 and a composite molecular sieve that comprises molecular sieve MCM-22 and zeolite A selected from at least one of ZSM-22, ZSM-23 and ZSM-48, wherein, the molecular sieve MCM-22 covers around the zeolite A. The present invention further provides a catalyst and an application of the catalyst. The catalyst comprises a carrier and a noble metal loaded on the carrier, wherein, the carrier comprises a modified composite molecular sieve that is the modified composite molecular sieve provided in the present invention or the modified composite molecular sieve obtained with the method provided in the present invention. The catalyst that utilizes the composite molecular sieve as a carrier not only can decrease the solidifying point of waxy raw oil, but also can improve the yield of liquid product, is especially applicable to the isomerization dewaxing process of lube distillate, and has an advantage of remarkably improving the viscosity index of lube base oil.

The present invention provides a modified composite molecular sieve, and a preparation method and an application of the modified composite molecular sieve. The modified composite molecular sieve comprises SiO.sub.2 and a composite molecular sieve that comprises molecular sieve MCM-22 and zeolite A selected from at least one of ZSM-22, ZSM-23 and ZSM-48, wherein, the molecular sieve MCM-22 covers around the zeolite A. The present invention further provides a catalyst and an application of the catalyst. The catalyst comprises a carrier and a noble metal loaded on the carrier, wherein, the carrier comprises a modified composite molecular sieve that is the modified composite molecular sieve provided in the present invention or the modified composite molecular sieve obtained with the method provided in the present invention. The catalyst that utilizes the composite molecular sieve as a carrier not only can decrease the solidifying point of waxy raw oil, but also can improve the yield of liquid product, is especially applicable to the isomerization dewaxing process of lube distillate, and has an advantage of remarkably improving the viscosity index of lube base oil.

The hydroisomerization catalyst of the present invention is a catalyst used for hydroisomerization of a hydrocarbon, including a support including a calcined zeolite modified with at least one metal selected from the group consisting of Na, K, Cs, Mg, Ca, Ba, and K, and having a thermal history that includes heating at 350 C. or more, and at least one inorganic oxide selected from the group consisting of alumina, silica, titania, boria, zirconia, magnesia, ceria, zinc oxide, phosphorus oxide, and a composite oxide containing a combination of at least two or more of these oxides; and at least one metal supported on the support and selected from the group consisting of elements belonging to Groups 8 to 10 of the periodic table, molybdenum and tungsten.

Uses for a family of new crystalline molecular sieves designated SSZ-91 are disclosed. Molecular sieve SSZ-91 is structurally similar to sieves falling within the ZSM-48 family of molecular sieves, and is characterized as: (1) having a low degree of faulting, (2) a low aspect ratio that inhibits hydrocracking as compared to conventional ZSM-48 materials having an aspect ratio of greater than 8, and (3) is substantially phase pure.

Uses for a family of new crystalline molecular sieves designated SSZ-91 are disclosed. Molecular sieve SSZ-91 is structurally similar to sieves falling within the ZSM-48 family of molecular sieves, and is characterized as: (1) having a low degree of faulting, (2) a low aspect ratio that inhibits hydrocracking as compared to conventional ZSM-48 materials having an aspect ratio of greater than 8, and (3) is substantially phase pure.

The present disclosure is directed to processes using a new crystalline molecular sieve designated SSZ-96, which is synthesized using a 1-butyl-1-methyl-octahydroindolium cation as a structure directing agent.

The present disclosure is directed to processes using a new crystalline molecular sieve designated SSZ-96, which is synthesized using a 1-butyl-1-methyl-octahydroindolium cation as a structure directing agent.

A feed mixture comprising one or more xylene isomers may be separated in a p-xylene recovery unit using simulated moving bed, chromatography with toluene as a desorbent to obtain a product stream rich in p-xylene and a raffinate stream lean in p-xylene. Optionally, an intermediate stream may be obtained as well. At least a portion of the raffinate stream or an isomerized raffinate stream may be separated in a distillation column to produce an overhead, stream comprising toluene, which may be fed to the p-xylene recovery unit as at least a portion of the desorbent. If present, the intermediate stream may be isomerized under liquid-phase isomerization conditions and fed to the p-xylene recovery unit. At least a portion of the raffinate stream or one or more lower streams obtained from the distillation column may be isomerized under liquid-phase isomerization conditions and fed to the p-xylene recovery unit.

A feed mixture comprising one or more xylene isomers may be separated in a p-xylene recovery unit using simulated moving bed, chromatography with toluene as a desorbent to obtain a product stream rich in p-xylene and a raffinate stream lean in p-xylene. Optionally, an intermediate stream may be obtained as well. At least a portion of the raffinate stream or an isomerized raffinate stream may be separated in a distillation column to produce an overhead, stream comprising toluene, which may be fed to the p-xylene recovery unit as at least a portion of the desorbent. If present, the intermediate stream may be isomerized under liquid-phase isomerization conditions and fed to the p-xylene recovery unit. At least a portion of the raffinate stream or one or more lower streams obtained from the distillation column may be isomerized under liquid-phase isomerization conditions and fed to the p-xylene recovery unit.