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 the catalyst composition under conversion conditions effective to dealkylate and transalkylate said C.sub.8+ aromatic hydrocarbons to produce said lighter aromatic products comprising benzene, toluene and xylene. The catalyst composition comprises a zeolite, a first metal, and a second metal, and is treated with a source of sulfur and/or a source of steam.

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 process for the conversion of plant oils, animal fats, waste food oils and carboxylic acids into renewable liquid fuels, such as bio-naphtha, bioQAV and renewable diesel, for use in combination with fossil fuels. The process is composed of two steps: hydrotreatment and hydrocracking. The effluent from the hydrotreatment step contains aromatics, olefins and compounds resulting from the polymerization of esters and acids. This is due to the use of partially reduced catalysts without the injection of a sulfiding agent and allows for the production of bioQAV of suitable quality for use in combination with fossil kerosene. Concurrently, the process generates, in addition to products in the distillation range of naphtha, kerosene and diesel, high molecular weight linear paraffins (up to 40 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 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.

A method for preparing liquid fuel by direct conversion of syngas uses the syngas as reaction raw material and conducts a catalytic conversion reaction on a fixed bed or a moving bed. The catalyst is a composite catalyst formed by compounding component I and component II in a mechanical mixing mode. The active ingredient of the component I is a metal oxide, and the component II is at least one of zeolites with one-dimensional ten-membered ring porous channels; and a weight ratio of the active ingredient in the component I to that in the component II is 0.1-20. The reaction process has high product yield and selectivity. The selectivity for liquid fuel composed of C.sub.5-C.sub.11 can reach 50-80%. The selectivity for aromatic hydrocarbon is less than 40% in C.sub.5-C.sub.11, while the selectivity for methane side product is less than 15%.

The invention relates to the production of aromatic hydrocarbon by the conversion of a feed comprising C.sub.2+ non-aromatic hydrocarbon, e.g., natural gas. The invention is particularly useful in converting natural gas to liquid-phase aromatic hydrocarbon, which can be more easily transported away from remote natural gas production facilities. The conversion is carried out in the presence of a dehydrocyclization catalyst comprising dehydrogenation and molecular sieve components. The dehydrocyclization catalyst has an average residence time of 90 seconds or less.

The invention relates to converting non-aromatic hydrocarbon in the presence of CO.sub.2 to produce aromatic hydrocarbon. CO.sub.2 methanation using molecular hydrogen produced during the aromatization increases aromatic hydrocarbon yield. The invention also relates to equipment and materials useful in such upgrading, to processes for carrying out such upgrading, and to the use of such processes for, e.g., natural gas upgrading.

The invention relates to the production of aromatic hydrocarbon by the conversion of a feed comprising saturated hydrocarbon. At least a portion of the saturated hydrocarbon is converted to olefinic hydrocarbon. Aromatic hydrocarbon is produced from at least a portion of the olefinic hydrocarbon using at least one dehydrocyclization catalyst comprising dehydrogenation and molecular sieve components.

A catalyst for preparing aviation fuel from synthetic oil obtained by Fischer-Tropsch process, including: between 20 and 50 percent by weight of an amorphous aluminum silicate, between 5 and 20 percent by weight of alumina, between 20 and 60 percent by weight of a hydrothermally modified zeolite, between 0.5 and 1.0 percent by weight of a Sesbania powder, between 0.5 and 5 percent by weight of nickel oxide, and between 5 and 15 percent by weight of molybdenum oxide. The invention also provides a method for preparing the catalyst.

The invention relates to converting non-aromatic hydrocarbon in the presence of CO.sub.2 to produce aromatic hydrocarbon. CO.sub.2 methanation using molecular hydrogen produced during the aromatization increases aromatic hydrocarbon yield. The invention also relates to equipment and materials useful in such upgrading, to processes for carrying out such upgrading, and to the use of such processes for, e.g., natural gas upgrading.