Disclosed are processes for conversion of a feedstock comprising C.sub.8+ aromatic hydrocarbons to lighter aromatic products in which the feedstock and optionally hydrogen are contacted in the presence of a first and a second catalyst composition under conversion conditions effective to produce said lighter aromatic products comprising benzene, toluene and xylene. In the process, the C.sub.8+ aromatic hydrocarbons are dealkylated to form C.sub.6-C.sub.7 aromatic hydrocarbon and the C.sub.2+ olefins formed are saturated. The remaining C.sub.8+ aromatic hydrocarbons are transalkylated with the C.sub.6-C.sub.7 aromatic hydrocarbon. The first and second catalyst compositions each comprise a zeolite, a first metal, and optionally a second metal, and are treated with a source of sulfur and/or a source of steam.

The present invention relates to a catalyst comprising a macroporous noble metal-containing zeolite material and a porous SiO.sub.2-containing binder, wherein the catalyst has a proportion of micropores of more than 70%, based on the total pore volume of the catalyst. The invention is additionally directed to a process for preparing the catalyst and to the use of the catalyst as an oxidation catalyst.

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 crystalline molecular sieve selected from at least one of ZSM-22, ZSM-23 and ZSM-48, wherein, the molecular sieve MCM-22 covers around the crystalline molecular sieve. 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 process for preparing a zeolite by hydrothermal heating of silica precursor and alumina precursor along with a combination of two structure-directing organic templates, N,N-dimethyl formamide and 1,6-diaminohexane in the presence of an alkali. The use of two structure-directing organic templates, not only reduces the crystallization time but also enables the preparation of more catalytically active ZSM-22 of submicron crystallite size. The present invention also provides a process of preparing a noble metal containing zeolite catalyst for hydroisomerization of long chain n-paraffins.

The present invention relates to a zeolite comprising platinum. The invention furthermore relates to a method for producing said zeolite comprising platinum according to the invention, to the use of said zeolite as an oxidation catalyst and hydrocarbon reservoir and to a catalyst component comprising the zeolite according to the invention.

Disclosed are a method for preparing a noble metal hydrogenation catalyst comprising preparing a carrier from a molecular sieve having a 10-member ring structure and/or an amorphous porous material; preparing a noble metal impregnation solution; and preparing noble metal impregnation solutions in a concentration gradient ranging from 0.05 to 5.0 wt % with deionized water, and sequentially impregnating the carrier with the impregnation solutions from low to high concentrations during the carrier impregnation process, or preparing a noble metal impregnation solution at a low concentration ranging from 0.05 to 0.5 wt % and impregnating the carrier by gradually increasing the concentration of the noble metal impregnation solution to 2.0 to 5.0 wt % in the impregnation process, followed by homogenization, drying, and calcination, as well as a noble metal hydrogenation catalyst, use thereof, and a method for preparing lubricant base oil.

A method for modification of pretreated acidic porous material via selective cation exchange using suitable solvent to obtain higher noble metal dispersion is described herein. The solvent system required for cation exchange should have its dielectric constant in the range of 25-45, wherein this solvent property is found to impart significant effect on cation loading and distribution, which in turn defines the stability, dispersion of the noble metals. The catalyst so obtained has higher noble metal dispersion and when used for hydroisomerization reaction, leads to higher selectivity even at significantly high conversion values.

The present invention relates to a catalyst comprising a macroporous noble metal-containing zeolite material and a porous SiO.sub.2-containing binder, wherein the catalyst has a proportion of micropores of more than 70%, based on the total pore volume of the catalyst. The invention is additionally directed to a process for preparing the catalyst and to the use of the catalyst as an oxidation catalyst.

Disclosed is a catalyst composition and its use in a process for the conversion of a feedstock containing C.sub.8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene. The catalyst composition comprises a first zeolite having a constraint index of 3 to 12, a second zeolite comprising a mordenite zeolite synthesized from TEA or MTEA, at least one first metal of Group 10 of the IUPAC Periodic Table, and at least one second metal of Group 11 to 15 of the IUPAC Periodic Table, wherein said mordenite zeolite has a mesopore surface area of greater than 30 m.sup.2/g and said mordenite zeolite comprises agglomerates composed of primary crystallites, wherein said primary crystallites have an average primary crystal size as measured by TEM of less than 80 nm and an aspect ratio of less than 2.

A method for producing a base oil for lubricant oils comprising: a first step of hydrocracking a petroleum slack wax having a content percentage of a heavy matter having 30 or more carbon atoms of 80% by mass or more and a content percentage of an oil of 15% by mass or less so that a crack per mass of the heavy matter is 5 to 30% by mass to obtain a hydrocracked oil comprising the heavy matter and a hydrocracked product thereof; and a second step of obtaining the base oil for lubricant oils from the hydrocracked oil.