Abstract: A process is described for the hydrided of halogen-substituted compounds of the second to fourth period of Groups III to V of the periodic system, with the exception of gallium, aluminum, carbon, or nitrogen. A finely-granulated aluminum is added to a molten salt melt that consists of 50-67 molar % AlCl.sub.3 (anhydrous) and 50 to 33 molar % of sodium chloride. Then to the stirred, or by some other means dispersed suspension, hydrogen is introduced to hydrided the finely-dispersed aluminum. Thereafter the mixture is reacted with the halogen-substituted compound and the resulting hydrided compound is renewed.

Abstract: A process of producing a silanic or siloxanic compound containing at least one cycloalkyl ring by the hydrogenation of a corresponding compound containing at least one aromatic ring, in the presence of a Raney nickel catalyst having a granulometry comprised essentially between 10 and 150 micrometers and a surface area of at least 80 m.sup.2 /g.

Abstract: The present invention provides a method for increasing the yield of methyldichlorosilane obtained from the reaction of silicon metal with methyl chloride without substantially decreasing the combined yield of methyldichlorosilane and dimethyldichlorosilane. This is achieved by blending the methyl chloride with an amount of hydrogen chloride sufficient to accomplish this without forming significant amounts of undesirable SiCl.sub.4 and/or HSiCl.sub.3. In accordance with a preferred embodiment of the present method the concentration of hydrogen chloride is from 0.1 to about 3 weight percent, based on methyl chloride. Most preferably the hydrogen chloride is present only from the first 50% to about 90% of the methyl chloride addition.

Abstract: The present invention provides a method for reducing the concentration of methyltrichlorosilane in the mixture of methylchlorosilanes obtained from the direct process reaction of silicon metal with a mixture of methyl chloride and hydrogen chloride. The method comprises blending the methyl chloride/hydrogen chloride mixture with from 0.1 up to about 5 weight percent of hydrogen, based on the methyl chloride.

Abstract: A process for recovering and recycling elementary silicon from a direct process organohalosilane reactor system is provided, comprising the steps of analyzing a portion of effluent contact mass, such as the silicon fines from a secondary cyclone with a particle size distribution analyzer, determing the fines fractions containing the relatively greatest amounts of impurities and segregating a relatively impure fine fraction from a purer coarse fraction with the aid of an aerodynamic centrifugal classifier.