Production method of silane

Abstract

The invention discloses a production method of silane. The production method comprises the following steps of: heating trichlorosilane to 70-90 DEG C by using a preheater; feeding heated trichlorosilane into a first reaction region of a reaction rectifying tower, and performing a first step catalytic disproportionation reaction of trichlorosilane in the first reaction region to generate dichlorosilane and silicon tetrachloride; feeding silicon tetrachloride generated in the first reaction region into the stripping section of the reaction rectifying tower, separating, purifying and discharging from a tower kettle; raising dichlorosilane generated in the first reaction region to a second reaction region of the reaction rectifying tower, and performing a second step catalytic disproportionation reaction to generate trichlorosilane and silane; refluxing the trichlorosilane generated in the second reaction region into the first reaction region, mixing with trichlorosilane heated by using the preheater, and continually performing the first step catalytic disproportionation reaction; and raising silane generated in the second reaction region into the rectifying section of the reaction rectifying tower, separating, purifying and discharging from the tower top of the reaction rectifying tower to obtain silane.

Description

technical field [0001] The embodiment of the present invention relates to a production method of chemical products, in particular to a production method of silane. Background technique [0002] The structure of silane is SiH 4 , also known as monosilane and silicon tetrahydrogen, is a foul-smelling colorless gas at normal temperature and pressure, and explosively burns in air or halogen gas. Silane has a wide range of uses. It is called industrial grade silane with a purity of 99.9% to 99.99%. It is mainly used in the production of special glass in the glass industry. It is electronic grade silane with a purity of 99.999%. industry; flat panel display; amorphous silicon thin-film solar cell industry; high-purity polysilicon growth; preparation of silicon nitride and silicon carbide micropowder, etc. High-purity silane is mainly concentrated in REC GROUP of the United States, accounting for 80% of the world. Other major manufacturers include MEMC Corporation of the United S...

AI Technical Summary

Problems solved by technology

[0008] The main advantages of the silicon-magnesium alloy method are: a long history, simple process flow, and intermittent production; its disadvantages are: the economic value of the by-product magnesium chloride is not high, and the energy consumption of sludge dehydration is high; batch production is difficult to produce on a large scale; liquid ammonia It is difficult to separate the magnesium hexachloride complex and ammonia; the circulation of ammonia is large, and a large amount of cooling capacity needs to be added, and the energy consumption is high.

Its main disadvantages are: the primary conversion rate of the disproportionation reaction is low, so the circulation of chlorosilane is large: in the production of 5000 tons / year of silane, the circulation of trichlorosilane is 65.2 tons / hour, such a large circulation will lead to high energy consumption and high equipment investment

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