A kind of preparation method of antimony

Abstract

The invention provides a preparation method of antimony. The preparation method comprises the following steps of: mixing antimony trichloride and hydrochloric acid; then rectifying; then reducing the rectified antimony trichloride to obtain the antimony. According to the preparation method, the volume ratio of SbCl3 to the hydrochloric acid is (150-800):1, so that the mass content of arsenic contained in the prepared antimony is lower than 20 ppb and far lower than the content of the arsenic contained in the raw material antimony trichloride, and the purity of the antimony is 99.9999%.

Description

technical field [0001] The invention relates to the field of metallurgical purification, in particular to a method for preparing antimony. Background technique [0002] High-purity antimony refers to metal antimony whose mass fraction of antimony is not less than 99.999%. It is mainly used for the preparation of semiconductor materials, such as chlorine antimonide, gallium antimonide and indium antimonide, etc., and can also be used as a component of high-purity alloy single crystal silicon or germanium. Therefore, high-purity antimony has strict requirements on the content of impurities in ppm and ppb levels, especially the content of arsenic. [0003] So far, there are two main methods for producing high-purity metal antimony: one is to use hydrochloric acid to pickle antimony compounds to obtain antimony trichloride solution, and then distill, rectify, and hydrogen reduce to obtain high-purity antimony; the other is to use chlorine gas and chlorine Antimony products in t...

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Problems solved by technology

But, the arsenic content in the antimony prepared by this method is relatively high, and the recovery rate of the product of this method is also low, only 78.%; CN1676638 discloses a kind of chloride that utilizes chlorine gas chlorination industrial antimony product to obtain antimony, and then After dechlorination and four-stage rectification, metal antimony with different purity is obtained, and the four rectification towers used in the rectification are all tray-type rectification towers.

Although metal antimony of different purity has been obtained in this patent, there are still following problems and shortcomings in the technology: (1) the chlorination process requires higher equipment, and the chlorine flow rate is too large to react too violently, which is difficult to control and is unsafe. If the chlorine flow rate is small, the chlorination output is small, and it is difficult to ensure the environment of the chlorine workshop. (2) Due to the continuous production, SbCl 3 The melting point is high (73.4°C), and the solution crystallizes to block the entire pipeline during pipeline transportation. Once the pipeline is blocked, the entire set of equipment will stop running; (3) In order to obtain antimony with different purity, 4 trays are used in the patent. The rectification tower requires large equipment investment and lengthy process; (4) The 99.9999% high-purity antimony prepared in this patent contains 160ppb arsenic, and the arsenic content is still high, which limits its application in the semiconductor and electronic fields

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