Abstract: The invention relates to a method for producing dimeric and/or trimeric silicon compounds, in particular silicon halogen compounds. The claimed method is also suitable for producing corresponding germanium compounds. The invention also relates to a device for carrying out said method to the use of the produced silicon compounds.

Abstract: The invention relates to a method for producing hexachlorodisilane or Ge2CI6, which is characterized in that, in a gas containing SiCI4 or GeCI4, a) a non-thermal plasma is generated by means of an alternating voltage of the frequency f, and wherein at least one electromagnetic pulse having the repetition rate g is coupled into the plasma, the voltage component of which pulse has an edge steepness in the rising edge of 10 V ns-1 to 1 kV ns-1 and a pulse width b of 500 ns to 100 ?s, wherein a liquid phase is obtained, and b) pure hexachlorodisilane or Ge2Cl6 is obtained from the liquid phase.

Abstract: The invention relates to a method for producing dimeric and/or trimeric silicon compounds, in particular silicon halogen compounds. The claimed method is also suitable for producing corresponding germanium compounds. The invention also relates to a device for carrying out said method to the use of the produced silicon compounds.

Abstract: The present invention relates to a process for producing SiO2 mouldings, comprising the preparation of a free-flowing aqueous SiO2 composition, solidification of the aqueous SiO2 composition and drying of the solidified SiO2 composition, wherein the aqueous SiO2 composition is a self-assembly composition. The present invention further relates to a moulding obtainable by the process according to the invention.

Abstract: The present invention relates to a process for preparing aqueous colloidal silica sols of high purity from silicate solutions, to aqueous colloidal silica sols with a specific profile of impurities, and to the use thereof. The invention further encompasses high-purity aqueous silica obtained as an intermediate in the course of the purification process, high-purity silicon dioxide obtainable by dewatering, and the use thereof.

Abstract: The invention relates to a process for preparing monochlorosilane by reaction of monosilane and dichlorosilane in the presence of a catalyst. In the process of the invention, monochlorosilane is formed by comproportionation of monosilane and dichlorosilane. The invention further relates to the use of the monochlorosilane produced and also a plant for carrying out the process.

Abstract: A reactor and a plant containing the reactor for conducting a continuous, industrial process for preparing high-purity silicon tetrachloride or high-purity germanium tetrachloride is provided. The plant contains a plasma reactor having a dielectric, a high voltage electrode and an earthed, metallic heat exchanger, in which the longitudinal axes of the dielectric, of the high-voltage electrode and of the earthed, metallic heat exchanger are oriented parallel to one another and at the same time parallel to the force vector of gravity.

Abstract: The present invention relates to an improved process for producing silicon, preferably solar silicon, using novel high-purity graphite mouldings, especially graphite electrodes, and to an industrial process for production of the novel graphite mouldings.

Abstract: A method for modification of a methane-containing gas stream, comprising the steps of: i) withdrawal of at least one substream from a methane-containing gas stream; ii) treatment of the substream with an electrically generated plasma, generating a modified gas composition which comprises a lower fraction of methane than the methane-containing gas stream used and iii) return of modified gas composition into the methane-containing gas stream. This method makes possible the storage of excess power in a natural gas line grid.

Abstract: The present invention relates to processes for industrial pyrolysis of a carbohydrate or carbohydrate mixture with addition of amorphous carbon, to a pyrolysis product thus obtainable and to the use thereof, especially as a reducing agent in the production of silicon from silica and carbon at high temperature.

Abstract: A reactor, a plant, and a continuous, industrial process carried out therein for preparing high-purity silicon tetrachloride or high-purity germanium tetrachloride by treating the silicon tetrachloride or germanium tetrachloride to be purified, which is contaminated by at least one hydrogen-containing compound, by a cold plasma and isolating purified high-purity silicon tetrachloride or germanium tetrachloride from the resulting treated phase by fractional distillation. The treatment is carried out in a plasma reactor in which longitudinal axes of a dielectric, of a high-voltage electrode, and of a grounded, metallic heat exchanger are oriented parallel to one another and at the same time parallel to the force vector of gravity.

Abstract: The present invention relates to a process for producing surface-modified water-absorbing polymer structures, comprising the process steps of providing a multitude of water-absorbing polymer structures and treating the surface of the water-absorbing polymer structures with a plasma and mixing a filler with the water-absorbing polymer structures. The invention also relates to an apparatus for this process, to the surface-modified water-absorbing polymer structures obtainable by this process, to a composite comprising these surface-modified water-absorbing polymer structures and a substrate, to a process for producing a composite, to a composite obtainable by this process, to chemical products comprising these surface-modified water-absorbing polymer structures or the composite, and to the use of the surface-modified water-absorbing polymer structures or of the composite in chemical products.

Abstract: The invention relates to a complete method for producing pure silicon that is suitable for use as solar-grade silicon, comprising the reduction of a purified silicon oxide using one or more pure carbon sources, the purified silicon oxide, which was purified as silicon oxide dissolved in an aqueous phase, having a content of other polyvalent metals or metal oxides, in relation to the silicon oxide, of less than or equal to 300 ppm, preferably less than 100 ppm, especially preferably less than 50 ppm and according to the invention less than 10 ppm of the other metals and being obtained advantageously by gel formation in alkaline conditions. The invention also relates to a formulation containing an activator and to the use of purified silicon oxide together with an activator for producing silicon.

Abstract: The invention relates to a complete method for producing pure silicon that is suitable for use as solar-grade silicon, comprising the reduction of a silicon oxide, purified by acidic precipitation from an aqueous solution of a silicon oxide dissolved in an aqueous phase, using one or more pure carbon sources, the purified silicon oxide being obtained, in particular, by the precipitation of a silicon oxide dissolved in an aqueous phase in an acidifier. The invention also relates to a formulation containing an activator and to a device for producing silicon, a reactor and electrodes.

Abstract: The present invention relates to a system for producing silicon, preferably high-purity silicon, particularly solar silicon, and to a method for producing silicon, preferably high-purity silicon, in particular solar silicon, in each case with particularly effective resource utilization and reduced emission of pollutants.

Abstract: The object of the invention is a more energy-efficient system for utilizing waste heat and residual gases from the engineered generation of carbon compounds, such as carbon black, graphite or from sugar pyrolysis, using a coupling of energy-heat or a thermal heat-generating plant for generating electrical energy, in particular for operating melt furnaces, and/or for utilizing the waste heat in endothermal processes. The invention also relates to the use of waste heat.

Abstract: The present invention relates to methods for the technical pyrolysis of a carbohydrate or carbohydrate mixture at an elevated temperature while adding silicon oxide, to a pyrolysis product obtainable in this way, and to the use thereof as a reducing agent for the production of solar silicon from silicic acid and carbon at a high temperature.

Abstract: The invention relates to a method for producing silicon carbide through reaction of silicon oxide and a carbon source comprising a hydrocarbon at high temperature, in particular to a technical method for producing silicon carbide or for producing compositions containing silicon carbide. The invention further relates to a high-purity silicon carbide, to compositions containing the same, to the use thereof as a catalyst and for the production of electrodes and other items.

Abstract: The invention relates to a plant for carrying out chemical processes comprising at least means for directly carrying out the conversion in the form of means for developing products and/or in the form of at least one reactor for the continuous industrial manufacture of products, devices for receiving and/or providing starting materials and/or products and devices for controlling the conversion, which are combined to a single integrated and transportable functional unit serving as infrastructure, preferably in the form of a standardised transport container.

Abstract: The invention relates to a method for producing silicon by reacting silicon oxide at an elevated temperature, silicon carbide and, optionally, a second carbon source being added to the reaction mixture. The invention further relates to a composition that can be used in the disclosed method. The essential part of the invention is the use of silicon carbide as a reaction initiator and/or reaction accelerator during the production of silicon or, alternatively, in nearly equimolar amounts for the production of silicon.