Method for making alkylhalosilanes
AssigneeGeneral Electric Company
InventorsWilliam J. Ward, III, Alan Ritzer, Kenneth M. Carroll, John W. Flock
Life of this patent
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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.
Claims28
A method for making alkylhalosilanes comprising effecting reaction between an alkyl halide and powdered silicon in the presence of an effective amount of a copper-zinc-tin catalyst.
A method for making methylchlorosilanes which substantially enhances the rate of dimethyldichlorosilane formation, while substantially reducing the weight ratio of methyltrichlorosilane to dimethyldichlorosilane, and maintaining or reducing the percent by weight of products in the resulting methylchlorosilane crude having a boiling point of greater than 70.degree. C. at atmospheric pressure which comprises,
- effecting reaction between methyl chloride and powdered silicon in a reactor in the presence of an effective amount of a copper-zinc-tin catalyst produced by the introduction of a mixture of powdered silicon, copper, or copper compound, zinc or zinc compound, and tin or tin compound, where the copper or copper compound, tin or tin compound, and zinc or zinc compound are introduced along with powdered silicon and methyl chloride, and the introduction of copper, tin and zinc or compounds thereof is effected at a rate sufficient to maintain in the reactor, a copper-zinc-tin catalyst having an average composition of 0.5-10% by weight copper relative to silicon, 200-3,000 ppm tin relative to copper and 0.01 part to 0.5 part of zinc per part of copper.
A powdered silicon-copper-zinc-tin contact mass comprising 0.5-10% by weight copper based on silicon, 200-3000 ppm of tin per part of copper and 0.01 part to 0.5 part of zinc per part of copper.
A copper-zinc-tin catalyst useful for making methylchlorosilane based on the reaction between methyl chloride and powdered silicon.
A method for making methylchlorosilanes which substantially enhances the rate of dimethyldichlorosilane formation while substantially reducing the weight ratio of methyltrichlorosilane to dimethyldichlorosilane and maintaining or reducing the percent by weight of products in the resulting methylchlorosilane crude having a boiling point of greater than 70.degree. C. at atmospheric pressure, which comprises effecting reaction between methyl chloride and powdered silicon in the presence of an effective amount of a copper-zinc-tin catalyst where the copper-zinc-tin catalyst comprises from 0.5 to 10% by weight of copper relative to silicon and 200-3000 ppm of tin and 0.01 part to 0.5 part of zinc per part of copper.
Dependencies are inferred from the claim text.