In a process for producing a methyl-substituted biphenyl compound, at least one methyl-substituted cyclohexylbenzene compound of the formula:

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wherein each of m and n is independently 1, 2, or 3, is contacted with hydrogen in the presence of a hydrogenation catalyst to produce a hydrogenation reaction product comprising at least one methyl-substituted bicyclohexane compound, and the methyl-substituted bicyclohexane compound is then contacted with a dehydrogenation catalyst to produce a dehydrogenation reaction product comprising at least one methyl-substituted biphenyl compound.

A molecular sieve has a silica/alumina molar ratio of 100-300, and has a mesopore structure. One closed hysteresis loop appears in the range of P/P.sub.0=0.4-0.99 in the low temperature nitrogen gas adsorption-desorption curve, and the starting location of the closed hysteresis loop is in the range of P/P.sub.0=0.4-0.7. The catalyst formed from the molecular sieve as a solid acid not only has a good capacity of isomerization to reduce the freezing point, but also can produce a high yield of the product with a lower pour point. The process for preparing the catalyst involves steps including crystallization, filtration, calcination, and hydrothermal treatment.

Methods are provided for activation of catalysts comprising low amounts of a hydrogenation metal, such as low amounts of a Group 8-10 noble metal. The amount of hydrogenation metal on the catalyst can correspond to 0.5 wt % or less (with respect to the weight of the catalyst), or 0.1 wt % or less, or 0.05 wt % or less. Prior to loading a catalyst into a reactor, the corresponding catalyst precursor can be first activated in a hydrogen-containing atmosphere containing 1.0 vppm of CO or less. The thus first-activated catalyst can be transferred to a reactor with optional exposure to oxygen during the transfer, where it can be further activated using a hydrogen-containing atmosphere containing 3.0 vppm of CO or higher, to yield a twice-activated catalyst with high performance. The catalyst can be advantageously a transalkylation catalyst or an isomerization catalyst useful for converting aromatic hydrocarbons.

To provide a structured catalyst for catalytic cracking or hydrodesulfurization that suppresses decline in catalytic activity, achieves efficient catalytic cracking, and allows simple and stable obtaining of a substance to be modified. The structured catalyst for catalytic cracking or hydrodesulfurization (1) includes a support (10) of a porous structure composed of a zeolite-type compound and at least one type of metal oxide nanoparticles (20) present in the support (10), in which the support (10) has channels (11) that connect with each other, the metal oxide nanoparticles (20) are present at least in the channels (11) of the support (10), and the metal oxide nanoparticles (20) are composed of a material containing any one or two more of the oxides of Fe, Al, Zn, Zr, Cu, Co, Ni, Ce, Nb, Ti, Mo, V, Cr, Pd, and Ru.

A process for reducing haze in a heavy base oil includes: obtaining a first effluent oil by contacting a hydrocarbon feedstock with a first catalyst including a zeolite of the ZSM-12 family; and obtaining a second effluent oil by contacting the first effluent oil with a second catalyst including a zeolite of the ZSM-48 family. A hydroisomerization catalyst system having reduced haze includes: a first catalytic region having a first catalyst disposed therein, the first catalyst including a zeolite of the ZSM-12 family; and a second catalytic region having a second catalyst disposed therein, the second catalyst including a zeolite of the ZSM-48 family. The first catalytic region is disposed upstream of the second catalytic region.

The invention concerns a catalyst comprising at least one zeolite with structure type MTW, a matrix, at least one metal from group VIII of the periodic classification of the elements, said catalyst having a mesopore volume increased by at least 10% compared with its initial mesopore volume, which is generally in the range 0.55 to 0.75 mL/g, at the end of a treatment with steam at a partial pressure in the range 0.01 to 0.07 MPa and at a temperature in the range 300 C. to 400 C. for at least 0.5 hour. The invention concerns the process for the preparation of said catalyst as well as an isomerization process employing said 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.

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 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.

An alkylaromatics isomerisation catalyst, which catalyst comprises at least 50 wt % of an inorganic binder; at least 0.01 wt % of a Group VIII metal and 1-9 wt % ZSM-12 zeolite wherein the silica to alumina molar ratio (SAR) of the ZSM-12 zeolite is in the range of from 60 to 200, and a process for the isomerisation of alkylaromatics to provide a reaction mixture, said process comprising contacting a hydrocarbon stream comprising alkylaromatics with such catalyst.