Process for preparing trichlorosilane by utilizing reverse disproportionation reaction

Abstract

The invention discloses a process for preparing trichlorosilane by utilizing reverse disproportionation reaction. The process is characterized by comprising the following steps: step (1): conveying silicon tetrachloride into a rectifying tower from the bottom of the rectifying tower, pumping out and sufficiently mixing with dichlorosilane in a static mixer after purifying, wherein a mass ratio of the dichlorosilane to the silicon tetrachloride is 1to 10; a step (2): feeding the silicon tetrachloride and the dichlorosilane which are sufficiently mixed in the step (1) into a fixed-bed reactor for reacting; and step (3): conveying a synthesis gas reacting in the fixed-bed reactor in the step (2) into the rectifying tower, wherein trichlorosilane is discharged from the middle position of the rectifying tower. According to the process disclosed by the invention, the raw materials, namely dichlorosilane and silicon tetrachloride with lower value are converted into trichlorosilane with a very high utilization value, so that material utilization rate is effectively increased; meanwhile, a problem that the dichlorosilane and the silicon tetrachloride are enriched is solved.

Description

technical field [0001] The invention relates to the field of trichlorosilane preparation, in particular to a process for preparing trichlorosilane by an anti-disproportionation reaction. Background technique [0002] Trichlorosilane is also known as trichlorosilane, silicon chloroform, English name: trichiorosilane or silicochioroform, molecular formula is SIHCL 3 , used in the synthesis of organosilanes and alkyl, aryl and organofunctional group chlorosilanes, is the most basic monomer in organosilane coupling agents, and is also the raw material for the production of semiconductor silicon, single crystal silicon and polycrystalline silicon. [0003] Anti-disproportionation technology is a process of consuming silicon tetrachloride and dichlorodihydrosilane to generate trichlorosilane at a certain temperature and pressure under a specific bed height equipped with a specific resin. At the same time, the process of separating the product by rectification, the principle is: f...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved in the present invention is to provide a process for preparing trichlorosilane by anti-disproportionation reaction, and convert the low-value raw materials dichlorodihydrosilane and silicon tetrachloride into high-value product trichlorosilane, Effectively improve the utilization rate of raw materials, and at the same time solve the problem of enrichment of dichlorodihydrosilane and silicon tetrachloride

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