Abstract: Silicon and silica values are obtained from recycled organosilicon products such as silicones, by introducing a recycle feed containing the organosilicon products into an electric furnace while producing metallurgical grade silicon from a silica source and a carbon source.

Abstract: Silicon and silica values are obtained from recycled organosilicon products such as silicones, by introducing a recycle feed containing the organosilicon products into an electric furnace while producing metallurgical grade silicon from a silica source and a carbon source.

Abstract: A process for refining crude molten silicon. The process includes oxidatively refining the crude molten silicon in the production of technical silicon. The crude molten silicon is admixed during the refining with a particulate mediator which has a minimum amount of metallic silicon of 8% by mass and also at least one or more of the elements H, C, O, F, Cl, Ca, Fe and Al. The particulate mediator is described by a characteristic number K which has a value of 0.03 to 6 mm?1 and is calculated using the formula K = 6 · ( 1 - ? m , M ) d 50 , M where d50,M is the particle size (diameter) at 50% of the mass undersize of the grading curve of the particulate mediator [mm] and the ?m,M is the mean effective porosity of the particulate mediator.

Abstract: A process for the oxidative refining of crude silicon melts during the production of technical-grade silicon. The process includes oxidative refining a crude silicon melt during the production of technical-grade silicon, where during the refining of the crude silicon melt, a finely divided mediator having a particle size parameter d50 of 1 to 200 ?m is added. The finely divided mediator contains a minimum content of metallic silicon of 8% by mass and also at least one or more of the elements H, C, O, F, Cl, Ca, Fe and Al. Additionally, the finely divided mediator is added to the crude silicon melt by means of pneumatic conveying with a gas.

Abstract: Silicon metal-containing agglomerates are produced by agglomerating a mixture of finely divided silicon metal-containing particles having a particle size parameter d50 of not more than 250 ?m and in the dry state a silicon metal content of at least 10% by mass, at least one binder containing 90% to 98% by mass of silicon dioxide and having a specific surface area of 15 to 35 m2/g, and water, wherein the mass ratio between finely divided silicon metal-containing particles and binder in the mixture is from 80/20 to 99/1, and the resulting moist agglomerates have a water content of 5% to 15% by mass, and drying the agglomerates.

Abstract: Technical silicon is produced by heating a raw material mixture comprising particulate silicon metal-containing material and a particulate mediator containing at least one of C, O, Al, Ca and Si, to at least 1490° C., forming a liquid silicon phase, and solidifying this phase, wherein the raw material mixture a characteristic number K of from 0.000 to 60, calculated as follows: K = m ? ( SiM ) · d ? ? 50 ? ( SiM ) + m ? ( Med ) · d ? ? 50 ? ( Med ) m ? ( SiM ) + m ? ( Med ) · ? ( equation ? ? 1 ) where m (SiM) is the mass of the silicon metal-containing material in the batch m (Med) is the mass of the mediator d50,SiM is the mean particle size of the silicon metal-containing material, d50,Med is the mean particle size of the mediator, and ? is the mean porosity of the silicon metal-containing material.

Abstract: Aluminum chloride is separated from a silane mixture containing aluminum chloride by reacting the aluminum chloride with a compound reactive therewith which forms an ionic liquid or solid, and separating the ionic liquid or solid from the now-purified silane.

Abstract: Impure gaseous hydrogen chloride from organochlorosilane hydrolysis is freed of impurities by first scrubbing with an organochlorosilane, which may be the same or different from the organochlorosilane(s) hydrolyzed, and then further scrubbing with chloromethane. The purified gaseous hydrogen chloride is preferably used in chlorosilane synthesis.

Abstract: Aluminum chloride is separated from a silane mixture containing aluminum chloride by reacting the aluminum chloride with a compound reactive therewith which forms an ionic liquid or solid, and separating the ionic liquid or solid from the now-purified silane.

Abstract: Cleaning industrial plant components to remove silane, metal halide, and organometallic halide contaminants and mixtures thereof, involves treating the plant components with a liquid nitrile or amine or mixture thereof or with a solution of a nitrile or amine or mixture thereof in an aprotic solvent.

Abstract: Impure gaseous hydrogen chloride from organochlorosilane hydrolysis is freed of impurities by first scrubbing with an organochlorosilane, which may be the same or different from the organochlorosilane(s) hydrolyzed, and then further scrubbing with chloromethane. The purified gaseous hydrogen chloride is preferably used in chlorosilane synthesis.

Abstract: Methylchlorosilanes are synthesized by an at least two stage reaction in which contact composition from a first fluidized bed reactor is fed to a second fluidized bed reactor.

Abstract: Alkyl chlorosilanes from the manufacture of dialkyldichlorosilanes are rearranged in continuous fashion to dialkyldichlorosilane by a rearrangement reaction in a moving bed reactor employing a solid alumina catalyst containing aluminum chloride, spent catalyst being continuously removed from the reactor.

Abstract: Pneumatic conveying of fine solids in the direct synthesis of alkylchlorosilanes conveying gas containing at least 50% by volume of alkyl chloride. The conveying apparatus preferably contains a means for switching conveying gas in the pneumatic conveying of fine solids.

Abstract: Alkyl chlorosilanes from the manufacture of dialkyldichlorosilanes are rearranged in continuous fashion to dialkyldichlorosilane by a rearrangement reaction in a moving bed reactor employing a solid alumina catalyst containing aluminum chloride, spent catalyst being continuously removed from the reactor.

Abstract: Cleaning industrial plant components to remove silane, metal halide, and organometallic halide contaminants and mixtures thereof, involves treating the plant components with a liquid nitrile or amine or mixture thereof or with a solution of a nitrile or amine or mixture thereof in an aprotic solvent.

Abstract: Distillation of silane mixtures in the presence of a nitrile, amine, or mixtures thereof, the nitrile and amine each having a boiling point of at least 120° C. at 1013 hPa, is effective to remove metal halide, organometal halides, and other contaminants.

Abstract: Pneumatic conveying of fine solids in the direct synthesis of alkylchlorosilanes conveying gas containing at least 50% by volume of alkyl chloride. The conveying apparatus preferably contains a means for switching conveying gas in the pneumatic conveying of fine solids.

Abstract: A process for hydrolyzing organochlorosilanes involves reacting organochlorosilanes with water in a tube bundle reactor to form a polyorganosiloxane-containing crude hydrolyzate and hydrogen chloride.

Abstract: Highly alkyl-substituted disilanes generally considered as uncleavable, obtained as part of the residue of alkylchlorosilane synthesis, are converted into cleavable disilanes having fewer alkyl groups by reaction with hydrogen halide in the presence of an alumina catalyst. The resulting disilanes can be cleaved into commercially valuable monosilanes by conventional processes.