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Organohalosilanes are prepared by charging a reactor with a contact mass of metallic silicon and a catalyst and feeding an organohalide-containing gas to the reactor. Tin or a tin compound is used as the catalyst. Then organohalosilanes can be produced quite efficiently at a high reaction rate while maintaining a low T/D ratio and minimizing the deposition of by-products and carbon.
A process for the preparation of carvone comprises hydrogenating carvoxime in the presence of a selecively poisoned catalyst. Preferred catalysts include noble metals supported on inorganic materials poisoned with a catalyst modifier. In a preferred embodiment of the process defined herein, the crude carvone reaction product produced in accordance with the process of the invention, is purified by treating the crude carvone product with an organometallic compound M(X).sub.n wherein M is a polyval...
For the preparation of organopolysiloxanes, water glass diluted with water to a concentration of 3 to 15 wt % is reacted with a triorganohalosilane in the presence of an acid and an oxygen-containing solvent such as isobutyl alcohol, methyl isobutyl ketone or 1-pentanol. The invention achieves a considerable reduction of the environmental load, an improved utilization of reactants, an improved yield, and a cost reduction, and enables production of low viscosity MQ resins.
Provided is a method for the preparation of desflurane wherein isoflurane is reacted with 0.7-1.2 mol. % of antimony pentachloride and 1.3-2.2 molar equivalents of hydrogen fluoride. Typically, the method is conducted by addition of hydrogen fluoride to a mixture of isoflurane and antimony pentachloride. After the addition of hydrogen fluoride is completed, the reaction is preferably maintained at temperatures of about 9-18.degree. C. for about 6 to 7 hours, before being quenched.
The present invention provides a process for preparing a terpyridine compound of the formula I ##STR1## by obtaining a C.sub.1 -C.sub.4 -alkyl pyridine-2-carboxylate derivative by acid hydrolysis of a 2-cyanopyridine derivative by means of an anhydrous inorganic acid or its anhydride in the presence of water and a C.sub.1 -C.sub.4 -alkanol, with an equimolar amount of water being added to the 2-cyanopyridine derivative prior to addition of the anhydrous inorganic acid or its anhydride, subsequen...
A continuous process for preparing alkylamines comprises reacting continuous streams of ammonia and alkyl halide in a molar ratio of at least 10:1 in a pressure reactor. The ultimate reaction mixture has a temperature of >80.degree. C., a pressure of >40 bar and an ammonium halide content of >1% by weight, and comprises two phases (A) a first phase comprising at least 75% by weight of the total amount of ammonium halide formed, and (B) a second phase comprising at least 80% by weight of...
A process for the preparation of transparent copolycarbonate is disclosed. The copolycarbonate the molecular structure of which contains more than 35 mole % of units derived from dihydroxydiphenylene is prepared by the melt transesterification process wherein the final temperature of the reaction is reached in less than 40 minutes after reaching the starting temperature.
Continuous process for preparing polyoxymethylene homo- or copolymers by bulk polymerization of the monomers in the presence of cationic initiators, and also, if desired, in the presence of regulators, where during the polymerization both the monomers and the polymer are present in molten form and, if desired, the polymer is then deactivated, and the melt is discharged, cooled and pelletized, which comprises discharging, cooling and pelletizing the polymer at an elevated pressure and in the pres...
The present invention relates to a process for the preparation of tetrahydrogeraniol, wherein the product mixtures and distillation residues from linalool, citronellal, citronellol or geraniol/nerol synthesis are fed directly to catalytic hydrogenation.
A polyethylene having improved rheological properties is disclosed. The polyethylene has a melt index (MI.sub.2) from about 0.01 dg/min to about 50 dg/min and a melt strength (.eta.) that satisfies MI.sub.2.times..eta..gtoreq.3.5. A process for making the polyethylene is also disclosed. The process uses an azaborolinyl-containing single-site catalyst in the presence of hydrogen, where the hydrogen consumption is controlled to be less than 30%.
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