HCl dehydration and purification method suitable for synthesis of trichlorosilane

Abstract

The invention discloses a method for dehydrating and purifying HCl suitable for the synthesis of trichlorosilane, comprising steps: 1) vaporizing silicon tetrachloride; 2) putting vaporized silicon tetrachloride and HCl in a silica separator 3) The mixed gas of silicon tetrachloride and HCl is heated and enters into the trichlorosilane synthesis furnace; 4) Part of the gaseous silicon tetrachloride enters directly into the trichlorosilane synthesis furnace from the silicon tetrachloride vaporizer In the chlorohydrogen silicon synthesis furnace, the present invention utilizes polysilicon production waste silicon tetrachloride to dehydrate HCl. This method is suitable for the existing trichlorosilane production system below 0.5MPa, which not only solves the problem of vaporization and In order to solve the problem of pipeline effusion, the two concepts of silicon tetrachloride dehydration and introduction of silicon tetrachloride into the trichlorosilane synthesis furnace to increase the production of trichlorosilane are skillfully combined; the production of by-product silicon tetrachloride is suppressed Generation, and then indirectly promoted the occurrence of the main reaction, improved the output of trichlorosilane.

Description

Technical field [0001] The present invention involves a method of dehydration and purification of HCL gas for polysilicon silicon production and increased silicon hydrochloride production. Specifically, the method of removing water in HCL with gas tetrachloride is used and can increase the production of silicon silicon. Background technique [0002] In recent years, with the rapid development of global new energy replacement and my country's solar photovoltaic industry, the demand for polysilicon market has experienced explosive growth, resulting in a situation of tight polysilicon lack.At present, the main raw material for the production of polysilicon to produce polysilicon is silicon, also known as coilsine. [0003] At present, the domestic method is mainly used to synthesize the silicon hydrochloride. The raw materials are industrial silicon powder and HCL gases.If the water content in the raw materials exceeds the standard, it will cause great harm to the entire trichloride...

AI Technical Summary

Problems solved by technology

[0004] (1) Corrosion equipment and pipelines;

[0005] (2) It is easy to cause pipeline blockage and cause system paralysis;

[0007] (4) Increase the unit consumption of silicon powder, thereby increasing the production cost

The cost of molecular sieve dehydration is very high, and the regeneration cycle is long, so there are certain limitations in the application of HCl dehydration in the polysilicon industry

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