Processes are described for separating 3,4′- and 4,4′-dimethylbiphenyl from a mixture comprising at least 3,3′-, 3,4′- and 4,4′-dimethylbiphenyl. In the processes, the mixture is cooled to produce a crystallization product comprising at least of the 4,4′-dimethylbiphenyl from the feed mixture and a first mother liquor product. The first mother liquor product is distilled to produce a bottoms stream enriched in 4,4′-dimethylbiphenyl as compared with the first mother liquor product and an overhead stream deficient in 4,4′-dimethylbiphenyl as compared with the first mother liquor product. The overhead stream is then cooled to produce a second crystallization product comprising at least part of the 3,4′-dimethylbiphenyl from the overhead stream and a second mother liquor product.

Processes are described for separating 3,4′- and 4,4′-dimethylbiphenyl from a mixture comprising at least 3,3′-, 3,4′- and 4,4′-dimethylbiphenyl. In the processes, the mixture is cooled to produce a crystallization product comprising at least of the 4,4′-dimethylbiphenyl from the feed mixture and a first mother liquor product. The first mother liquor product is distilled to produce a bottoms stream enriched in 4,4′-dimethylbiphenyl as compared with the first mother liquor product and an overhead stream deficient in 4,4′-dimethylbiphenyl as compared with the first mother liquor product. The overhead stream is then cooled to produce a second crystallization product comprising at least part of the 3,4′-dimethylbiphenyl from the overhead stream and a second mother liquor product.

In a process for producing a methyl-substituted biphenyl compound, at least one methyl-substituted cyclohexylbenzene compound of the formula: ##STR00001##
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.

In a process for producing a methyl-substituted biphenyl compound, at least one methyl-substituted cyclohexylbenzene compound of the formula: ##STR00001##
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.

In a process for producing a methyl-substituted biphenyl compound, at least one methyl-substituted cyclohexylbenzene compound of the formula: ##STR00001##
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.

The invention relates to polyoxometalates represented by the formula (A.sub.n).sup.m+[M′M.sub.12O.sub.y(RCOO).sub.zH.sub.q].sup.m− or solvates thereof, corresponding supported polyoxometalates, and processes for their preparation, as well as corresponding metal clusters, optionally in the form of a dispersion in a liquid carrier medium or immobilized on a solid support, and processes for their preparation, as well as their use in reductive conversion of organic substrate.

The invention relates to polyoxometalates represented by the formula (A.sub.n).sup.m+[M′M.sub.12O.sub.y(RCOO).sub.zH.sub.q].sup.m− or solvates thereof, corresponding supported polyoxometalates, and processes for their preparation, as well as corresponding metal clusters, optionally in the form of a dispersion in a liquid carrier medium or immobilized on a solid support, and processes for their preparation, as well as their use in reductive conversion of organic substrate.

The invention relates to polyoxometalates represented by the formula (A.sub.n).sup.m+[M′M.sub.12O.sub.y(RCOO).sub.zH.sub.q].sup.m− or solvates thereof, corresponding supported polyoxometalates, and processes for their preparation, as well as corresponding metal clusters, optionally in the form of a dispersion in a liquid carrier medium or immobilized on a solid support, and processes for their preparation, as well as their use in reductive conversion of organic substrate.

Bulk catalysts comprised of nickel, molybdenum, tungsten and titanium and methods for synthesizing bulk catalysts are provided. The catalysts are useful for hydroprocessing, particularly hydrodesulfurization and hydrodenitrogenation, of hydrocarbon feedstocks.

Bulk catalysts comprised of nickel, molybdenum, tungsten and titanium and methods for synthesizing bulk catalysts are provided. The catalysts are useful for hydroprocessing, particularly hydrodesulfurization and hydrodenitrogenation, of hydrocarbon feedstocks.