Boron separation from Si-Sn alloy by slag treatment

Rowaid Al-khazraji; Ya-qiong Li; Li-feng Zhang

doi:10.1007/s12613-018-1698-0

Volume 25 Issue 12

Dec. 2018

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2018 > 25(12): 1439-1446

Rowaid Al-khazraji, Ya-qiong Li, and Li-feng Zhang, Boron separation from Si-Sn alloy by slag treatment, Int. J. Miner. Metall. Mater., 25(2018), No. 12, pp. 1439-1446. https://doi.org/10.1007/s12613-018-1698-0

Cite this article as:

Rowaid Al-khazraji, Ya-qiong Li, and Li-feng Zhang, Boron separation from Si-Sn alloy by slag treatment, Int. J. Miner. Metall. Mater., 25(2018), No. 12, pp. 1439-1446. https://doi.org/10.1007/s12613-018-1698-0

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Research Article

Boron separation from Si-Sn alloy by slag treatment

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Corresponding author:
Ya-qiong Li E-mail: liyq_ustb@163.com
Received: 5 June 2018; Revised: 11 September 2018; Accepted: 13 September 2018

Abstract

Abstract

This study investigates a purification process for metallurgical-grade silicon (MG-Si) in which Si is alloyed with tin (Sn) and CaO-SiO₂-CaCl₂ slag is used to remove boron (B) impurity. Acid leaching was performed to remove the Sn phase after slag refining to recover high-purity Si from the Si-Sn alloy. The effect of refining time was investigated, and acceptable refining results were realized within 15 min. The effects of slag composition and Sn content on the removal of B were also studied. The results indicate that increasing Sn content favors B removal. With the increase of Sn to 50% of the alloy, the final B content decreased to 1.1×10^-4wt%, 93.9% removal efficiency.
- boron removal;
- metallurgical grade silicon;
- Si-Sn alloy;
- slag refining

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References

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