Abstract: The invention relates to a process for the catalytic hydrodehalogenation of SiCl4 to form HSiCl3, which comprises bringing a gaseous feed mixture comprising hydrogen and silicon tetrachloride into direct contact with at least one heating element of a resistance heating device, with the heating element being composed of a metal or a metal alloy and being heated to carry out the reaction.

Abstract: The invention relates to a method for producing a polysilane-polycarbosilane copolymer solution. Said method comprises the preparation of a polysilane, obtained by the disproportionation of a methylchlorodisilane or a mixture of methylchlorodisilanes of formula Si2MenC16-n with a Lewis base as the catalyst, a subsequent thermal cross-linking of the polysilane to form an infusible polysilane-polycarbosilane copolymer that is soluble in inert solvents, in addition to the production of said solution by the dissolution of the polysilane-polycarbosilane copolymer in an inert solvent. The invention also relates to a method for producing oxygen-depleted ceramic fibers and other molded bodies with a composition similar to that of SiC. Said method comprises the spinning of the solution to obtain green fibers according to the dry spinning method and the pyrolysis of the dried green fibers in an inert gas atmosphere or a reductive atmosphere.

Abstract: A process for producing borazane from boron-nitrogen and boron-nitrogen-hydrogen containing BNH-waste products. The process includes reacting the BNH-waste products with a hydrogen halide, having the formula HX, wherein X is selected from the group consisting of F, Cl, Br, I, and combinations thereof, to form any of the following: a boron trihalide, having the formula BX3, an ammonium halide, having the formula NH4X, and hydrogen. The boron trihalide is then reacted with the hydrogen to form diborane, having the formula B2H6, and hydrogen halide. The ammonium halide is then converted to ammonia, having the formula NH3, and hydrogen halide. The diborane is then reacted with the ammonia to form borazane, having the formula BH3NH3.

Abstract: The present invention relates to a for controlled synthesis of hydrogen-rich cyclosiloxanes of the (H2SiO)n type. where n is an integer equal to or greater than 3, by reacting: a.) a halosilane of the H2SiX2 type where X=halogen with b.) a lithium salt, copper(II) salt or a salt of a metal from main group 2 or transition group 2 of the periodic table of the elements, or a mixture of these salts. The ring size is advantageously adjustable to n=3, 4, 5, 6 (especially n=4 to 6), such that larger rings are not formed. In a particularly advantageous embodiment of the process, for the selective preparation of cyclohexasiloxane (H2SiO)6, after the reaction, the solvent is at least partly removed and then solvent is added again.

Abstract: The present invention relates to a for controlled synthesis of hydrogen-rich cyclosiloxanes of the (H2SiO)n type. where n is an integer equal to or greater than 3, by reacting: a.) a halosilane of the H2SiX2 type where X=halogen with b.) a lithium salt, copper(II) salt or a salt of a metal from main group 2 or transition group 2 of the periodic table of the elements, or a mixture of these salts. The ring size is advantageously adjustable to n=3, 4, 5, 6 (especially n=4 to 6), such that larger rings are not formed. In a particularly advantageous embodiment of the process, for the selective preparation of cyclohexasiloxane (H2SiO)6, after the reaction, the solvent is at least partly removed and then solvent is added again.

Abstract: The invention relates to a process for the catalytic hydrodehalogenation of SiCl4 to HSiCl3 in the presence of hydrogen, in which at least one metal or metal salt selected from among the elements of main group 2 of the Periodic Table of the Elements (PTE) is used as catalyst at a temperature in the range from 300 to 1 000° C. In particular, the catalyst is a metal or metal salt which forms stable metal chlorides under these conditions.

Abstract: The present invention pertains to a method for producing a polysilane-polycarbosilane copolymer solution, which comprises the preparation of a polysilane, obtained by the disproportionation of a methylchlorodisilane or a mixture of methylchlorodisilanes of the formula Si2MenCl6-n with a Lewis base as the catalyst, a subsequent thermal crosslinking of the polysilane to form an infusible polysilane-polycarbosilane copolymer that is soluble in inert solvents, as well as the production of said solution by the dissolution of the polysilane-polycarbosilane copolymer in an inert solvent. In addition, the present invention also pertains to a method for producing oxygen-depleted ceramic fibers and other molded bodies having a composition similar to that of SiC.

Abstract: A process for producing borazane from boron-nitrogen and boron-nitrogen-hydrogen containing BNH-waste products. The process includes reacting the BNH-waste products with a hydrogen halide, having the formula HX, wherein X is selected from the group consisting of F, Cl, Br, I, and combinations thereof, to form any of the following: a boron trihalide, having the formula BX3, an ammonium halide, having the formula NH4X, and hydrogen. The boron trihalide is then reacted with the hydrogen to form diborane, having the formula B2H6, and hydrogen halide. The ammonium halide is then converted to ammonia, having the formula NH3, and hydrogen halide. The diborane is then reacted with the ammonia to form borazane, having the formula BH3NH3.

Abstract: The invention relates to a process for the catalytic hydrodehalogenation of SiCl4 to form HSiCl3, which comprises bringing a gaseous feed mixture comprising hydrogen and silicon tetrachloride into direct contact with at least one heating element of a resistance heating device, with the heating element being composed of a metal or a metal alloy and being heated to carry out the reaction.

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.

Abstract: A process for producing oxygen-free or low-oxygen shaped bodies of silicon carbide, particularly SiC fibers, by using chemically reactive polysilanes and/or polycarbosilanes as precursors. In accordance with the invention green fibers are stabilized preferably in the presence of reactive gases.

Abstract: Catalysts composed of nitrogen-containing heterocyclic hydrocarbons, optionally fixed to a support material, for disproportionating aryl- and alkylhalodisilanes into the corresponding mono- and polysilanes, and a process of using these catalysts for disproportionating disilanes.