Abstract: Trichlorosilane production is increased while simultaneously lowering environmental burden due to destruction and disposition of high boilers by feeding high boilers from trichlorosilane production or from polycrystalline silicon production into a fluidized bed for production of trichlorosilane from metallic silicon and hydrogen chloride.

Abstract: The invention relates to a process for purifying chlorosilanes by distillation, which includes providing a boron-containing mixture of chlorosilanes containing TCS, DCS and STC and purifying the mixture of chlorosilanes by distillation in a plurality of distillation columns, wherein low-boiling boron compounds are branched off from the distillation columns by means of overhead streams containing boron-enriched DCS and high-boiling boron compounds are branched off by means of a boron-enriched bottom stream containing high boilers.

Abstract: The invention relates to a method for hydrolyzing hydrolyzable solid metallic salts, wherein the metallic salts are reacted with aqueous saline solutions.

Abstract: The invention relates to a method for hydrolyzing hydrolyzable metallic salts, the metallic salts being reacted with emulsions of a) water and b) an inert liquid.

Abstract: The invention relates to a method for hydrolyzing hydrolyzable metallic salts, the metallic salts being reacted with emulsions of a) water and b) an inert liquid.

Abstract: The invention relates to a method for hydrolyzing hydrolyzable solid metallic salts, the metallic salts being reacted with aqueous saline solutions.

Abstract: Highly pure pyrogenic silica is produced in an integrated polycrystalline silicon production plant by separating offgas from polycrystalline silicon production into a high boiler fraction, vaporizing this fraction into a pyrogenic silica burner and reacting with air and/or oxygen and hydrogen to form pyrogenic silica.

Abstract: Highly pure pyrogenic silica is produced in an integrated polycrystalline silicon production plant by separating offgas from polycrystalline silicon production into a high boiler fraction, vaporizing this fraction into a pyrogenic silica burner and reacting with air and/or oxygen and hydrogen to form pyrogenic silica.

Abstract: Trichlorosilane production is increased while simultaneously lowering environmental burden due to destruction and disposition of high boilers by feeding high boilers from trichlorosilane production or from polycrystalline silicon production into a fluidized bed for production of trichlorosilane from metallic silicon and hydrogen chloride.

Abstract: Hydrogenation of a chlorosilane takes place in a reactor having a graphite reaction chamber with a surface which contacts the chlorosilane and a graphite electric heating element which also contacts the chlorosilane, wherein an Si-containing compound and hydrogen are contacted with the reaction chamber and the heating element such that an SiC coating is formed in situ on their surfaces in a first process step, and hydrogenation of the chlorosilane is effected by heating of a chlorosilane/hydrogen mixture in the reaction chamber by means of the heating element in a second process step, the first process step carried out at a reaction temperature which is higher than the reaction temperature of the second process step.

Abstract: Hydrogenation of a chlorosilane takes place in a reactor having a graphite reaction chamber with a surface which contacts the chlorosilane and a graphite electric heating element which also contacts the chlorosilane, wherein an Si-containing compound and hydrogen are contacted with the reaction chamber and the heating element such that an SiC coating is formed in situ on their surfaces in a first process step, and hydrogenation of the chlorosilane is effected by heating of a chlorosilane/hydrogen mixture in the reaction chamber by means of the heating element in a second process step, the first process step carried out at a reaction temperature which is higher than the reaction temperature of the second process step.

Abstract: Catalytic dehalogenation (or hydrodehalogenation) of halogen-containing compounds of elements of group IV of the periodic table in the presence of hydrogen is carried out using a finely-dispersed catalytically active material which comprises silicon and at least one transition metal, and which is characterized by high catalytic activity and stability. This process can be used, for example, for synthesizing compounds or alternatively for decomposing halogen-containing compounds, for instance in waste-water or waste-gas purification processes. It is also suitable for dehalogenation (hydrodehalogenation) of halogen-containing silane compounds, for instance of silicon tetrachloride or alkyl trichlorosilane compounds, and the original purity of the silanes used as starting materials is retained by the products. Tetrachlorosilane, for example, can be converted into trichlorosilane.