Abstract: A method for controlling the direct process to vary the concentrations of trialkylhalosilanes and alkyltrihalosilanes in the product. The method comprises contacting an alkyl chloride with silicon metalloid in the presence of a catalytic amount of a catalyst comprising 0.5 to 10 weight percent copper, 5 to 200 ppm tin, 25 to 2,500 ppm phosphorous, and greater than zero to less than 50 ppm zinc, where the concentration of each of the catalyst components is based on the weight of the silicon, at a temperature within a range of about 250.degree. C. to 400.degree. C. The present inventors have found that by controlling the zinc concentration the concentrations of trialkylhalosilanes and alkyltrihalosilanes in the product can be varied.

Abstract: Silicon fines which have been recovered from an organochlorosilane reactor are treated with HCl or elemental chlorine at an elevated temperature to salvage chlorosilane and metal salt values. Passivation is also achieved.

Abstract: The invention relates to a silicon alloy intended for the production of alkyl or aryl halogenosilanes using the Rochow reaction, comprising, in percent by weight:0.05<Al<0.300.01<Ca<0.300.02<O.sub.2 <0.200.10<Fe<0.500.01<Ti<0.15x<Cu<2+xwhere x=3.2 (% Ca)+9.4 (% Al) the remainder being silicon. The alloy according to the invention makes it possible to improve the reactivity and the selectivity of the reaction.

Abstract: Siloxane fluids containing novel siloxane polymers prepared from mixtures of disilanes, disiloxanes and silylmethylenes, and a method for recovering fully alkylated linear and cyclic siloxanes with disilane, disiloxane and silylmethylene bonds, such as from methylchlorosilane residue cleavage bottoms, are disclosed.

Abstract: Metallic silicon for the Rochow-Synthesis is reduced to particles measuring at least 5 mm in their smallest dimension and 15 mm in their largest dimension, cooling the silicon from a temperature of at least 700.degree. C. to at most 120.degree. C. within a maximum of 2 seconds, and then ground and reacted.

Abstract: Alkenylchlorosilane of formula I and a direct synthesis thereof are disclosed, wherein silicon metal is reacted with mixed gas comprising alkenyl chloride of formula II and hydrogen chloride or alkyl chloride of formula III in the presence of copper catalyst at a temperature range from 220.degree. C. to 350.degree. C. ##STR1## In formula I, R.sub.1 represents hydrogen, methyl, SiHCl.sub.2, SiCl.sub.3 or CH.sub.2 SiCl.sub.3 and R.sub.2 represents hydrogen or chlorine. ##STR2## In formula II, R.sub.3 represents hydrogen or chlorine and R.sub.2 represents hydrogen, methyl or CH.sub.2 Cl.Cl--R.sub.5 (III)In formula III, R.sub.5 represents hydrogen, C.sub.1 -C.sub.4 alkyl or CH.sub.2 CH.sub.2 Cl.

Abstract: Methylchlorosilanes are prepared from silicon and methyl chloride in the presence of a copper catalyst and optionally promoter substances, the production rates of the individual methylchlorosilanes, based on the surface area of the silicon employed, being controlled by the structural parameter QF of the silicon. The structural parameter QF is determined by(a) cutting up silicon test specimens to form a cut surface.(b) totaling on the cut surface the areas of the precipitates of intermetallic phases having a longitudinal shape to give an area number A,(c) totaling on the cut surface the areas of precipitates of intermetallic phases having a circular shape to give an area number B, and(d) obtaining the quotient of the area number A and the area number B, called the structural parameter QF.

Abstract: A method is provided for passivating spent silicon contact mass by heating the spent silicon contact mass at a temperature in the range of from 200.degree. C. to 800.degree. C. in an oxygen containing atmosphere.

Abstract: The present invention is an improved process for the reaction of an alkyl halide with particulate silicon in a fluidized-bed process. The improvement comprises controlling the particle size of the silicon within a range of one micron to 85 microns. Preferred is when the particle size of the silicon has a mass distribution characterized by a 10th percentile of 2.1 to 6 microns, a 50th percentile of 10 to 25 microns, and a 90th percentile of 30 to 60 microns. Most preferred is when the particle size mass distribution of the silicon is characterized by a 10th percentile of 2.5 to 4.5 microns, a 50th percentile of 12 to 25 microns, and a 90th percentile of 35 to 45 microns. The process is run in the presence of a catalyst composition comprising copper and other catalysts.

Abstract: The present invention is an improvement of the Direct Process for the manufacture of alkylhalosilanes by the contact of powdered metallurgical grade silicon with an alkyl halide in the presence of a copper catalyst. The improvement reduces lot-to-lot variations in silicon conversion to desired dialkyldihalosilanes. The improvement comprises alloying 0.01 to nine weight percent copper with the silicon to be used in the process and separating slag. In a preferred embodiment of the present process, silicon-copper alloy is pulverized to a powder and mixed with additional copper and other catalysts to form a contact mass reactive with alkylhalides.

Abstract: A method is provided for passivating spent silicon contact mass by treating the spent silicon contact mass at a temperature in range of from 900.degree. C. to 1500.degree. C. in an inert atmosphere.

Abstract: A process for separating alkenes from a methylchlorosilane mixture by adding at least a stoichiometric amount of hydrogen chloride necessary for saturating the alkenes in the methylchlorosilane mixture and thereafter removing resulting chloroalkanes by distillation.

Abstract: A method of preparing an active silicon/copper contact mass for the direct reaction of organic halides with silicon to make organohalosilanes by contacting a particle size distribution of silicon with a copper catalyst vapor, aerosol or a combination of vapor and aerosol. The copper catalyst aerosol can be produced by rapid nucleation of the vapor, by an exothermic reaction between copper metal and chlorine gas or by ultrasonic energy dispersion of a solution of a copper compound to a fine mist consisting of extremely fine particles 0.1 to 0.01 micron or smaller. The preferred copper catalyst is copper chloride. The small, sub-micron size copper chloride aerosol provides an efficient utilization of copper to form the active Cu-Si alloys on the silicon particles' surfaces.

Abstract: A method for making organohalosilanes is provided utilizing spent contact mass generated during the production of organohalosilanes by the direct method which has been treated in an oxygen containing atmosphere to render it non-pyrophoric in air.

Abstract: A method for making organohalosilanes is provided utilizing a spent contact mass generated during the production of organohalosilanes by the direct method which has been thermally treated to render it non-reactive in air.

Abstract: The described invention is a process for preparing silanes from the reaction of solid silicon monoxide with aromatic halides. The solid silicon monoxide is reacted with the aromatic halide in the presence of a catalyst which can increase the conversion of silicon monoxide to silanes, and partially select for arylsilane products. The process may employ an activation step in which the solid silicon monoxide is activated by heating in an inert atmosphere. Activation of the solid silicon monoxide can increase silicon conversion and increase selectivity for arylsilane products.

Abstract: Dimethyldichlorosilane is selectively and directly synthesized by reacting methyl chloride with silicon in the presence of (.alpha.) a catalytically effective amount of metallic copper or a copper compound and a promoter (.beta.) therefor, such promoter (.beta.) comprising (.beta..sub.1) metallic tin and/or metallic anitmony or a tin and/or antimony compound, optionally, (.beta..sub.2) metallic zinc or a zinc compound, and (.beta..sub.3) at least one lanthanide compound; alternatively, the promoter (.beta.) comprises (.beta..sub.1), optionally, (.beta..sub.2), (.beta..sub.3) and (.beta..sub.4) at least one alkali metal or alkali metal compound.

Abstract: A process for the preparation of alkyl halogenosilanes comprising reacting silicon with alkyl halide in the presence of a copper catalyst and promoter substances and phosphorous and phosphorous compounds in combination with indium or indium compounds or aluminum or aluminum compounds or a mixture of aluminum or aluminum compounds and indium or indium compounds.

Abstract: This invention discloses a method of treating silicon with non-volatile, phosphorous compounds to allow the silicon to be used in the direct process for the manufacture of alkylhalosilanes. The treatment of the silicon is carried out by feeding phosphorous compounds to the silicon during or after refining.

Abstract: A process for the preparation of alkylhalogenosilanes by reaction of silicon with an alkyl halide in the presence of a copper catalyst and promoter substances, the improvement wherein gaseous phosphorus compounds are admixed, as promotor substances, with the stream of alkyl halide.

Abstract: The present invention is a process for preparing silanes from the reaction of solid silicon monoxide with organic halides. The solid silicon monoxide is reacted with the organic halide in the presence of a catalyst which can increase the conversion of silicon monoxide to silanes and partially select for the type of silanes produced. The process may employ an activation step in which the solid silicon monoxide is activated by heating in an inert atmosphere. Activation of the silicon monoxide can increase silicon conversion and alter the type of silanes produced.

Abstract: In the production of organochlorosilanes by reaction of silicon with an alkyl- and/or arylchloride in the presence of a copper catalyst and, optionally, promoter elements, the improvement wherein the silicon has been atomized with an inert gas, has a particle size of less than about 1000 .mu.m, by weight has an Al content of about 0.05 to 0.38%, a Ca content of about 0.02 to 0.2% and an Fe content of about 0.25 to 0.55%.

Abstract: Direct Synthesis processes for the selective production of organohalohydrosilanes at high rates, selectivities and conversions by the catalytic reaction of activated silicon with mixtures of organohalides and hydrogen in the presence of controlled concentrations of selected metal atoms.

Abstract: The present invention provides a method for reducing the concentration of methyltrichlorosilane obtained during the reaction of silicon metal with methyl chloride without substantially decreasing the combined yield of methyldichlorosilane, dimethylchlorosilane and dimethyldichlorosilane. The methyl chloride is blended with from 0.05 up to about 44 mole percent of hydrogen, based on combination of methyl chloride and hydrogen. At hydrogen concentrations above about 12 mole percent there is a substantial increase in the methyldichlorosilane content of the reaction product while the concentration of methyltrichlorosilane in the reaction product is maintained below about 4 percent by weight.

Abstract: This invention discloses a method of treating silicon with non-volatile, phosphorous compounds to allow the silicon to be used in the direct process for the manufacture of alkylhalosilanes. The treatment of the silicon is carried out by feeding phosphorous compounds to the silicon during or after refining.

Abstract: What is disclosed is a method of improving the performance of the direct process for preparing alkylhalosilanes using an alkylhalide and silicon. The method is based on the control of the phosphorous that enters the silicon used in the direct process, by controlling the amount of phosphorous that enters the silicon during the manufacture of the silicon itself.

Abstract: In the production of an organochlorosilane by reaction of silicon or a silicon alloy with an alkyl or aryl chloride in the presence of a copper catalyst, the improvement which comprises employing the silicon or alloy in atomized form.

Abstract: An improved Direct Reaction process which comprises reacting an organohalide with an activated silicon composition, the improvement comprising maintaining the composition of the activated silicon so that it comprises, based on the amount of silicon, 0.05-10 wt. % catalyst; an effective amount of promoter, and 0.001-0.1 wt. % tin, wherein the promoter to tin ratio is 10-250. Activated silicon compositions and methods for selecting a catalyst composition also are provided.

Abstract: There is provided a method and a catalyst for the direct production of organohalosilanes from elemental silicon and an alkylhalide. The catalytic material is characterized by the presence therein of zinc, the source of zinc in said catalyst being selected from the group consisting of zinc carbonate, zinc formate, zinc acetate, zinc vinyl acetate, zinc propionate, zinc butyrate, zinc beta-chlorobutyrate and zinc gamma-chlorobutyrate. These sources of zinc overcome problems encountered with zinc metal and zinc halides, commonly used as sources of zinc.

Abstract: What is disclosed is a method for controlling a process for the preparation of alkylhalosilanes from silicon and alkyl halides where metal arsenides and alloys of arsenic are used as promoters to enhance selectivity, overall yields of usable silanes, and silicon utilization. Also, disclosed is a composition comprising a direct reaction silicon/copper contact mass which includes arsenic as a component.

Abstract: Dimethyldichlorosilane is selectively and efficiently prepared by reacting methyl chloride with a solid contact mass comprising silicon and a catalytically effective amount of copper or a copper compound, said copper catalyst comprising (i) from about 10 to 1000 ppm of tin, antimony, or admixture thereof, or of a tin or antimony compound, or admixture thereof, (ii) from about 0.01 to 2% by weight of at least one of the metallic additives beryllium, calcium and magnesium, or compound thereof, and, optionally, (iii) from about 0.01 to 3% by weight of zinc or a zinc compound.

Abstract: Dimethyldichlorosilane is directly prepared from methyl chloride and silicon, in high productivity, selectivity and degree of silicon conversion, by reacting methyl chloride with a solid contact mass comprising silicon and a catalytically effective amount of a catalyst which includes (1) elemental copper or a copper compound, (2) from about 30 to 1,000 ppm (calculated as metallic tin and/or antimony) of at least one of the metals tin and antimony, or at least one compound of at least one of the metals tin and antimony, and (3) from about 0.05 to 4% by weight, (calculated as cesium metal) of cesium or a cesium compound, or admixture of cesium with up to 90% by weight of the admixture of lithium, sodium, potassium or rubidium, the amounts of said components (2) and (3) being based upon the total weight of said solid contact mass.

Abstract: Dimethyldichlorosilane is directly prepared from methyl chloride and silicon, in high productivity, selectivity and degree of silicon conversion, by reacting methyl chloride with a solid contact mass comprising silicon and a catalytically effective amount of a catalyst which includes (1) elemental copper or a copper compound, (2) from about 30 to 1,000 ppm (calculated as metallic tin and/or antimony) of at least one of the metals tin and antimony, or at least one compound of at least one of the metals tin and antimony, and (3) from about 0.05 to 2% by weight, (calculated as alkali metal) of at least one of the alkali metals lithium, sodium, potassium and rubidium, or compound thereof, the amounts of said components (2) and (3) being based upon the total weight of said solid contact mass.

Abstract: Dimethyldichlorosilane is selectively and efficiently prepared by reacting methyl chloride with a solid contact mass comprising silicon and a catalytically effective amount of copper or a copper compound, said copper catalyst comprising (i) from about 10 to 1000 ppm of tin, antimony, or admixture thereof, or of a tin or antimony compound, or admixture thereof, (ii) from about 0.01 to 2% by weight of at least one of the metallic additives barium and strontium, or compound thereof, and, optionally, (iii) from about 0.01 to 3% by weight of zinc or a zinc compound.

Abstract: What is disclosed is a method of controlling a process for the preparation of alkylhalosilanes from silicon and alkylhalides where phosphorous or certain phosphorous compounds are used as promoters to enhance selectivity, overall yields of useable silanes and enhanced silicon metal conversion.

Abstract: The use of fumed silica in a mixture of powdered silicon and cuprous chloride has been found to reduce agglomeration in a fluid bed reactor during the production of alkylhalosilane under continuous conditions.

Abstract: A method is provided for making alkylhalosilanes by effecting reaction between an alkyl halide, such as methyl chloride and powdered silicon in the presence of a copper-zinc-tin catalyst. Significant improvements in reaction rate and product selectivity are achieved when copper is employed at a critical weight percent relative to silicon and critical weight ratios of tin and zinc are employed relative to copper.

Abstract: A process is provided for making methylchlorosilanes based on the reaction of methylchloride and particulated silicon, which has been contacted with a mixture of partially oxidized copper catalyst and copper formate. A reduction is achieved in the percent by weight of residue which are the silicon products in the methylchlorosilane crude having boiling points exceeding 70.degree. C. at atmospheric pressure, while the weight percent of disilane in such residue cleavable to useful chlorosilane monomer is not adversely affected.

Abstract: Tetraalkyl orthosilicates may be prepared in good yield by contacting an alkanol having 1 to about 4 carbon atoms with copper-activated silicon synthesized by heating a mixture of cupric oxide and silicon particles at elevated temperatures at a temperature of about 120.degree.-250.degree. C. under autogeneous pressure.

Abstract: An improved direct process for producing organohalosilanes and particularly diorganodihalosilanes from silicon metal and an organohalide comprising contacting the two reactants in the presence of a partially oxidized copper catalyst having a surface area of at least 3.5 m.sup.2 /gm and wherein 100% of the particles are less than 35 microns in size and wherein 100% of the particles are over 0.7 microns in size.

Abstract: This invention relates to a method of separating close-boiling chlorosilanes from mixtures by employing the technique of liquid extraction with sulfolane and a hydrocarbon compound as co-solvents. The hydrocarbon compound employed is substantially immiscible in sulfolane and is present in sufficient amounts so that two liquid phases are formed, one being suloflane-rich and the other being hydrocarbon-rich. The mixture of chlorosilanes is intimately mixed with the two solvents and allowed to partition between the two phases. The preferred liquid extraction procedure is where the sulfolane and hydrocarbon solvent are in a countercurrent relationship within an extraction tower. Experimentally determined selectivity coefficients show that mixtures of (1) dimethyldichlorosilane and methyltrichlorosilane, (2) phenylmethyldichlorosilane and phenyltrichlorosilane, and (3) trimethylchlorosilane and tetrachlorosilane can be successfully separated by the techniques of this invention.

Abstract: An improved method for the separation of close-boiling chlorosilanes is described. The method consists of the extractive distillation of the close-boiling chlorosilanes using sulfolane as the extractive solvent and thereafter separating the higher-boiling chlorosilane and sulfolane by distilling the higher-boiling chlorosilane from the higher-boiling chlorosilane and sulfolane mixture to which is added a hydrocarbon solvent. Preferred hydrocarbon solvents include normal-heptane, normal-nonane, and 2,2,4-trimethylpentane. The sulfolane obtained from the higher-boiling chlorosilane and sulfolane mixture is suitable for recycling to the extractive distillation process as the sulfolane contains only limited amounts of dissolved chlorosilane.

Abstract: There is provided an improved process for removing residual silicon and copper powder from the gaseous organohalosilane products of a direct process reactor which utilizes sintered metal filtering elements to filter out the said powder from gaseous organoalosilanes which have been processed in primary and secondary cyclones.

Abstract: A copper catalyzed silicon reaction mass for the production of methylchlorosilane which comprises free-flowing powders or particles of silicon metal having spots of a copper-silicon alloy substantially uniformly distributed on the surface of the silicon particles, the copper constituting less than about 2% and preferably about 1.75% by weight of the catalytic mass.

Abstract: A process for recovering and recycling elementary silicon from a direct process organohalosilane reactor system is provided, comprising the steps of analyzing a portion of effluent contact mass, such as the silicon fines from a secondary cyclone with a particle size distribution analyzer, determing the fines fractions containing the relatively greatest amounts of impurities and segregating a relatively impure fine fraction from a purer coarse fraction with the aid of an aerodynamic centrifugal classifier.

Abstract: A process for treating certain particles of less than 40 microns average diameter size in a silicone reactor where methyl chloride is reacted with particles of silicon in the presence of copper to produce chlorosilanes comprising removing particles of less than 40 microns average diameter size; and abraiding said particles to remove the surface coating; and returning said particles to the reactor.

Abstract: A method is provided for making alkylhalosilanes by effecting reaction between an alkyl halide, such as methyl chloride and powdered silicon in the presence of a copper-zinc-tin catalyst. Significant improvements in reaction rate and product selectivity are achieved when copper is employed at a critical weight percent relative to silicon and critical weight ratios of tin and zinc are employed relative to copper.