Abstract:
The invention concerns a process for the preparation of a catalyst for carrying out hydrogenation reactions in hydrotreatment and hydrocracking processes. Said catalyst is prepared from at least one mononuclear precursor based on molybdenum (Mo), in its monomeric or dimeric form, having at least one Mo═O or Mo—OR bond or at least one Mo═S or Mo—SR bond where [R=CxHy where x≧1 and (x−1)≦y≦(2x+1) or R=Si(OR′)3 or R=Si(R′)3 where R′=Cx′Hy′ where x′≧1 and (x′−1)≦y′≦(2x′+1)], and optionally from at least one promoter element from group VIII. Said precursors are deposited onto an oxide support which is suitable for the process in which it is used, said catalyst being dried at a temperature of less than 200° C. then advantageously being sulphurized before being deployed in said process.
Abstract:
Gold (I) hydroxide complexes of the form Z—Au—OH and digold complexes of the form Z—Au-(μOH)—Au—Z where groups Z are two electron donors are provided. The groups Z may be carbenes, for example nitrogen containing heterocyclic carbenes (NHCs), phosphines or phosphites. The complexes can be used as catalysts, for example in reactions such as hydration of nitriles, skeletal arrangement of enynes, alkoxycyclization of enynes, alkyne hydration, the Meyer-Shuster reaction, 3,3′ rearrangement of allylic acetates, cyclization of propargylic acetates, Beckman rearrangements and hydroamination. The complexes can be used in medicine, for example in the treatment of cancer.
Abstract:
The invention concerns a process for the preparation of a catalyst based on tungsten intended for hydrotreatment or hydrocracking processes.The invention concerns a process for the preparation of a catalyst for carrying out hydrogenation reactions in hydrotreatment and hydrocracking processes. Said catalyst is prepared from at least one mononuclear precursor compound based on tungsten (W), in its monomeric or dimeric form, having at least one W═O or W—OR bond or at least one W═S or W—SR bond where [R═CxHy where x≧1 and (x−1)≦y≦(2x+1) or R═Si(OR′)3 or R═Si(R′)3 where R′═Cx′Hy′ where x′≧1 and (x′−1)≦y′≦(2×t+1)], optionally at least one Mo precursor and optionally at least one promoter element from group VIII. Said precursors are deposited onto an oxide support which is suitable for the process in which it is used, said catalyst advantageously being sulphurized before being deployed in said process.
Abstract:
According to the present invention, a method of producing ethers, which includes subjecting a conjugated diene compound and an alcohol to a telomerization reaction in the presence of a composition containing a palladium compound, an isocyanide represented by the formula (I) R1R2R3CNC (I) and a base represented by the formula (II) M(OR4)n (II) as a catalyst is provided. According to the method of the present invention, by telomerization reaction of a conjugated diene compound and an alcohol, ethers can be produced industrially advantageously. (In the above-mentioned formulas, each symbol is as defined in the specification.)
Abstract:
The present invention relates to catalytic compositions for esterification, transesterification and polycondensation reactions, a process for the catalysis of said reactions employing such catalytic compositions and polyesters or resins obtainable by this process.
Abstract:
The invention concerns an organometallic compound of formula RO-M(L1)X (L2)Y (L3)Z wherein M is a metal selected from titanium, zirconium, hafnium, iron (III), cobalt (III) or aluminium; L1 and L2 are each independently selected from a diketonate, an ester or amide of acetoacetic acid, a hydroxycarboxylic acid or ester thereof, R1COO— where R1 is substituted or unsubstituted C5-C30 branched or linear alkyl, substituted or unsubstituted aryl including polycyclic structures such as naphthyl or anthracyl, phosphate, phosphinate, phosphonate, siloxy or sulphonato, provided that when L1 is a ligand which forms two covalent bonds with the metal atom, and x=1 then y=0; L3 is selected from substituted or unsubstituted aryloxy, R2COO— where R2 is a linear or branched C6-C30 alkyl or a substituted or unsubstituted aryl, a polyoxyalkyl or hydroxyalkoxyalkylgroup; R is alkyl or hydroxy-alkyl hydroxyalkoxyalkyl, or (hydroxy)polyoxyalkyl group, x, y and z are each either 0 or 1 (x+y+z)≦V−1, where V=the valency of the metal M. The invention further concerns compositions and processes for the manufacture of polyurethane articles using the organometallic compounds as catalysts to provide cured articles having a comparable performance to those produced using a commercial mercury-based catalyst.
Abstract:
The invention describes materials comprising organic groups containing sulphur and phosphorous bonded together by a hydrocarbon chain and bonded via phosphorous and oxygen atoms to a mineral oxide of an element M, said materials being characterized in that they comprise M-O-M′ bonds, M′representing an element of a mineral oxide identical to or different from M, in that the ratio of the element M to the phosphorous is about 0.5: 1 to about 500:1 and in that each phosphorous atom of the phosphorous-containing groups forms at least one P—O-M bond and/or P—O-M′ bond. The invention also describes a process for preparing such materials.
Abstract:
Dehydroxylated oxide (e.g. silica) particles are obtained by reacting oxide particles, having surface hydroxyl groups, with a dialkylcarbonate or diarylcarbonate. The resulting products have surface alkoxy or aryloxy groups and significantly reduced hydroxyl content. The treated oxide particles are especially suitable for use as catalyst supports, and especially as polyolefin catalyst supports.
Abstract:
A hydrogenation catalyst consisting essentially of (A) at least one bis(cyclopentadienyl)titanium compound represented by the formula (1): ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, represent halogen atoms, hydrocarbon groups, aryloxy groups, alkoxy groups or carbonyl groups, and (B) at least one lithium compound represented by the formula (2):R.sup.3 O--Li (2)wherein R.sup.3 represents a hydrocarbon group, or a reaction mixture of an organolithium compound with an alcoholic or phenolic hydroxyl group-containing compound, the (A) component/the (B) component molar ratio being 1/0.5 to 1/20, and optionally (C) at least one reducing organometallic compound selected from the group consisting of aluminum compounds, zinc compounds and magnesium compounds, the (A) component/the (C) component molar ratio being 1/0.5 to 1/20. The above hydrogenation catalyst is effectively applied to the hydrogenation of a polymer having olefinic double bonds to produce a hydrogenated polymer having a high degree of hydrogenation at a high hydrogenation rate with a high reproducibility.
Abstract:
The invention relates to a method for preparing compositions having a high degree of elasticity under suddenly applied stress by mixing a composition containing diorganopolysiloxanes in which a few siloxane units or silanes are present which have a functionality higher than the functionality of the diorganopolysiloxane units with a condensation catalyst obtained from the reaction of dialkyldialkoxysilanes and tin carboxylates.