CS207859B1 - Silicon mixture for making the alcylchlorsilanes - Google Patents

Description

(54) Silicon compound for the production of alkyl chlorosilanes

The invention relates to a silicon mixture for carrying out the synthesis of alkyl chlorosilanes, in particular methyl chlorosilane.

The synthesis of alkyl chlorosilanes is carried out under pressure by combining the alkyl chloride with the copper-catalysed silicon powder and other additives such as cadmium and zinc compounds. These additions increase silicon yield. This material is prepared by fusing silicon with copper and other metals such as cadmium, titanium and the like.

We have found that a significantly better synthesis result will give a silicon composition containing what other promoter powdered antimony metal and non-salts thereof in an amount of 0.001 to 0.1% by weight of antimony per total amount of the composition. It is preferred that the mixture be as fine as possible and well homogenized.

In the synthesis according to the invention, better yields and in particular a more favorable desired ratio of the dimethyldichlersilane to methyltrichlorosilane fraction are obtained. The advantage of the method according to the invention results from the examples given.

Example 1

A slurry mixture was introduced into the process chlorosilane synthesis reactor

2071858,

207 OSO

460 kg of silicon powder 40 kg of electrolytic copper kg of zinc chloride 20 g of metallic antimoau powder and saturated under pressure and heating with methyl chloride. There were obtained 1,990 liters of methyl chlorosilanes having a content of 70% by weight. % dimethyldichlerailane, 25 wt. methyltrichlorosilane,

1.5% trimethylchlorailane and 2% palpation. methyldiohorsilane at an hourly rate of 43.21 / h * Example 2

A mixture of 460 kg silicon powder kg kg of electrolytic copper g of metallic antimony powder was charged to the reactor and methyl chloride was introduced under the same conditions. There were obtained 1,820 l of crude methylohlereilanes of 78% dimethyldichlorosilane, 18X methyltrichlorosilane, 3X trimethylchlorosilane and 0.5 methyldichlorosilane at a rate of 53.52 l / h.

Comparative. example

Mixture and composition 460 kg of silicon powder kg of electrolytic copper 2 kg of magnesium chloride were reacted with methyl chloride under the same conditions as in Example 1 and 2. 1,255 liters of crude methyl ethyl chlorosilanes of 25% by weight are obtained. % dimethyldiohorsilane, 52% wt. methyl trichlorosilane, 8X trimethylohlorsilane, 7% methyldichlorosilane at 33.2 l / h.

Claims (2)

MEASUREMENT OF THE INVENTION Silicon mixture for the production of alkyl chlorilanes, in particular methyl chlorosilanes from silicon powder and known catalysts, characterized in that it contains, as a further promoter, powdered metal antimony and / or salts thereof in an amount of 0.001 to 0.1% by weight. antimony to the total amount of the mixture. 2 ’. The silicon composition of claim 1, wherein at least 70% of the composition has a grain size of less than 90 microns.