Abstract: The present invention relates to a process for purifying low molecular weight hydridosilane solutions, in which a solution to be purified comprising a) at least one low molecular weight hydridosilane, b) at least one solvent and c) at least one impurity selected from the group of the compounds having at least 20 silicon atoms and/or the group of the homogeneous catalyst systems is subjected to a crossflow membrane process with at least one membrane separation step using a permeation membrane.

Abstract: The invention relates to a process for producing hydrogen-containing chlorosilanes by reducing Si-based deposits of solid material during the operation of a pressurised reactor comprising one or more reaction spaces, wherein at least one organochlorosilane is reacted with hydrogen in at least one of these reaction spaces for at least some of the time, characterized in that at least one of the optionally two or more reaction spaces in which this reaction takes place is supplied with additional HCl for at least some of the time. The additional HCl is preferably produced by hydrodehalogenation of silicon tetrachloride with hydrogen in at least one of the optionally two or more reaction spaces of the reactor.

Abstract: The invention relates to a process for producing a product gas mixture containing hydrogen-containing chlorosilanes within an integrated process by hydrogenating integrated process by-product silicon tetrachloride and organochlorosilane, more particularly methyltrichlorosilane, with hydrogen in a pressurized hydrogenation reactor comprising one or more reaction spaces each consisting of a reactor tube of gastight ceramic material, wherein the product gas mixture is worked up and at least a portion of at least one product of the product gas mixture is used as starting material for the hydrogenation or as starting material for some other process within the integrated process. The invention further relates to an integrated system useful for practising the integrated process.

Abstract: The invention relates to a process for preparing trichlorosilane, characterized in that hydrogen and at least one organic chlorosilane are reacted in a reactor which is operated under superatmospheric pressure and comprises one or more reactor tubes which consist of a gastight ceramic material.

Abstract: Process for preparing higher hydridosilanes of the general formula H—(SiH2)n—H where n?2, in which—one or more lower hydridosilanes—hydrogen, and—one or more transition metal compounds comprising elements of transition group VIII of the Periodic Table and the lanthanides are reacted at a pressure of more than 5 bar absolute, subsequently depressurized and the higher hydridosilanes are separated off from the reaction mixture obtained.

Abstract: The invention provides a process and apparatus for preparing chlorosilane from the reaction of very finely divided ultra-pure silicon with hydrogen chloride, the very finely divided ultra-pure silicon being fed into a solid bed of metallurgical silicon, the feed line for ultra-pure silicon and the fixed bed having a certain minimum temperature.

Abstract: The invention relates to a method for converting silicon tetrachloride by means of hydrogen to form trichlorosilane in a modified hydrodechlorination reactor. The invention further relates to a the use of such a modified hydrodechlorination reactor as an integrated component of a system for producing trichlorosilane from metallurgical silicon.

Abstract: The invention relates to the use of a ceramic heat exchanger as an integral part of a process for catalytic dehalogenation of silicon tetrachloride to trichlorosilane in the presence of hydrogen, wherein the product gas and the reactant gases are conducted as pressurized streams through the heat exchanger, and the heat exchanger comprises heat exchanger elements made from ceramic material.

Abstract: The present invention relates to a multistage process for preparing trichlorosilane and silicon tetrachloride from metallurgical silicon, in which trichlorosilane and silicon tetrachloride are prepared from metallurgical silicon in a first step, and the silicon tetrachloride is processed further to the trichlorosilane end product in a second step. The present invention further relates to a plant in which such processes can be performed in an integrated manner.

Abstract: The invention relates to a method for converting silicon tetrachloride having hydrogen to trichlorosilane in a hydrodechlorination reactor, wherein the hydrodechlorination reactor is operated under pressure and comprises one or more reactor tubes which are made of a ceramic material. The invention further relates to the use of such a hydrodechlorination reactor as an integral component of a system for producing trichlorosilane from metallurgical silicon.

Abstract: The present invention relates to a process for purifying low molecular weight hydridosilane solutions, in which a solution to be purified comprising a) at least one low molecular weight hydridosilane, b) at least one solvent and c) at least one impurity selected from the group of the compounds having at least 20 silicon atoms and/or the group of the homogeneous catalyst systems is subjected to a crossflow membrane process with at least one membrane separation step using a permeation membrane.

Abstract: Process for preparing higher hydridosilanes of the general formula H—(SiH2)n—H where n?2, in which—one or more lower hydridosilanes—hydrogen, and—one or more transition metal compounds comprising elements of transition group VIII of the Periodic Table and the lanthanides are reacted at a pressure of more than 5 bar absolute, subsequently depressurized and the higher hydridosilanes are separated off from the reaction mixture obtained.