Treatment process for purifying recycled hydrogen during production of electronic-grade polycrystalline silicon

Abstract

The invention relates to the field of gas separation and purification engineering, provides a treatment process for purifying recycled hydrogen during production of electronic-grade polycrystalline silicon and aims to solve the problem that the production of the electronic-grade polycrystalline silicon is influenced due to the fact that the content of impurities such as BCl3, borane, phosphine, PCl5, POCl3 and the like in hydrogen cannot be effectively reduced although activated carbon is adopted for absorbing and purifying recycled hydrogen during the production of the electronic-grade polycrystalline silicon. According to the purification scheme, the recycled hydrogen is pre-cooled and then cooled to the temperature below 0 DEG C, and then, the hydrogen is fed into a modified aluminum oxide absorber for impurity absorption and filtered by a filter, so that the purity of the hydrogen reaches 99.999% (V / V), and the production requirement of the electronic-grade polycrystalline silicon is met. The treatment process has the benefits of simplicity, easiness in operation, obvious purification effect and the like.

Description

technical field [0001] The invention relates to the field of high-purity recovery of tail gas in the production of electronic-grade polysilicon, the field of gas separation and purification engineering, and in particular to the field of high-purity recovery of tail gas in the production of electronic-grade polysilicon. Background technique [0002] In 2012, China imported 82,800 tons of polysilicon from Germany, the United States, South Korea and other countries, accounting for nearly 60% of the annual domestic demand. Domestic demand for electronic grade polysilicon is almost 100% dependent on imports. Electronic grade polysilicon is a basic functional material in industries such as electronic power, aerospace, and military industry. Although my country's polysilicon industry has developed rapidly in recent years, and its production capacity has leapt to the first place in the world, it is still unable to achieve mass production of electronic-grade polysilicon with a purit...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide an electronic-grade polysilicon for the problem that the content of impurities such as BCl3, borane, phosphine, PCl5, POCl3 in the recovered hydrogen cannot be effectively reduced, resulting in the inability to mass-produce electronic-grade polysilicon Purification process of hydrogen recovery in production, so that the recovery of hydrogen can meet the production needs of electronic grade polysilicon

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