Device for preparing trichlorosilane

Abstract

The invention discloses a device for preparing trichlorosilane. The device comprises a rectifying tower, a silicon tetrachloride discharge pipe arranged at the bottom of the rectifying tower and a silicon tetrachloride discharge pipe arranged on the rectifying tower, a fixed bed reactor connected with the silicon tetrachloride discharge pipe, a mixing pipe provided with a static mixer, a trichlorosilane discharge pipe arranged in the middle position of the rectifying tower and an impurity outflow pipe arranged at the top position of the rectifying tower, wherein the fixed bed reactor is also connected to a dichlorosilane feed pipe, and the silicon tetrachloride discharge pipe and dichlorosilane feed pipe are subjected to cooperation by the mixing pipe; the discharge outlet of the fixed bed reactor is connected to the upper part of the rectifying tower by a synthesis gas pipe, and the impurity outflow pipe is connected to the reflux tank of the rectifying tower. By virtue of two devices, dichlorosilane and silicon tetrachloride as byproducts in the improved Siemens production process are converted into trichlorosilane, the utilization of raw materials is improved and the problem of enrichment of dichlorosilane and silicon tetrachloride is solved.

Description

technical field [0001] The invention relates to the field of trichlorosilane preparation, in particular to a device for preparing trichlorosilane. 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: for a reversible reaction, when the volat...

AI Technical Summary

Problems solved by technology

[0005] For silicon tetrachloride, there are methods such as cold hydrogenation to treat it, so that it can be re-converted into trichlorosilane for reuse, but the domestic technology is immature, and the amount of silicon tetrachloride to be treated is large; Dihydrosilane, although there are relatively mature technologies abroad to prepare polysilicon using it as a raw material, due to technological blockade, this field is still almost blank in China, and the boiling point of dichlorodihydrosilane is relatively low, which is relatively dangerous.

Images