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pp 1–9 | Cite as

Purification of Metallurgical-Grade Silicon by Acid Leaching

  • Farzad Ebrahimfar
  • Mahdi Ahmadian
Original Paper
  • 8 Downloads

Abstract

Purification of metallurgical-grade silicon (MG-Si), used in many applications such as the medical industry, polymer industry and the solar cells manufacturing. Removal of impurities from MG-Si is critical in these applications. The MG-Si studied in the present research contained various iron, calcium, and aluminum impurities. The hydrometallurgical purification method with different types of acids as solvents was chosen to refine MG-Si. Effects of hydrochloric acid, hydrofluoric acid, sulfuric acid, nitric acid in combination with each other as a solvent for purification of MG-Si were investigated. Additionally, the effects of temperature and particle size of MG-Si were evaluated. In this study, in comparison with previous studies, samples with a larger particle size (in the range of 53 to 300 microns), less refining time (1 to 6 h) and relatively higher temperatures (30 to 70 C) were studied. The results indicated that the highest purity of MG-Si was achieved by HCl (25%) + HF (5%) and followed by HCl (25%) + H2SO4 (30%), HNO3 (25%) + HCl (25%), HNO3 (5%) and H2SO4 (25%), respectively. It was also found that with particle size 53μm, applying a temperature of 50 C for 6 h resulted in high efficiency and purity (99.96%) of MG-Si.

Keywords

Purification Hydrochloric acid Hydrofluoric acid Particle size Silicon 

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Notes

Acknowledgments

This research was conducted with the financial support of Akhgar Steel Company, Isfahan, Iran, and the Isfahan University of Technology.

References

  1. 1.
    Heuer M (2013) Metallurgical grade and metallurgically refined silicon for photovoltaics. Semicond Semimetals 89(2):77–134CrossRefGoogle Scholar
  2. 2.
    Hunt LP, Dosaj VD, Mc Cormick JR, Crossman LD (1976) Production of solar grade silicon from purified metallurgical silicon. IEEE Photovoltaic Spec Conf 12:125–129Google Scholar
  3. 3.
    Dietl J (1983) Hydrometallurgical purification of metallurgical-grade silicon. Sol Energy Mater Sol Cells 10 (2):145–154Google Scholar
  4. 4.
    Norman E, Absi E M, Raye A N D, Thomas E (1985) Solar-grade silicon substrates by a powder to ribbon process. Can J Phys 63(6):859–862CrossRefGoogle Scholar
  5. 5.
    Santos I C, Goncalves A P, Santos C S, Almeida M, Alfonso M H, Cruz M J (1990) Purification of metallurgical grade silicon by acid leaching. Hydrometallurgy 23(2):237–246CrossRefGoogle Scholar
  6. 6.
    Sahu S K, Asselin E (2012) Effect of oxidizing agents on the hydrometallurgical purification of metallurgical grade silicon. Hydrometallurgy 121–124(17):120–125CrossRefGoogle Scholar
  7. 7.
    Chu TL, Chu S (1983) Partial purification of metallurgical silicon by acid extraction. Electrochem 130:455–457CrossRefGoogle Scholar
  8. 8.
    Juneja JM, Mukherjee TK (1986) A study of the purification of metallurgical grade silicon. Hydrometallurgy 16:69–75CrossRefGoogle Scholar
  9. 9.
    Margarito F, Figueiredo MO (1988) Classifier: a quaternary Fe-Al-Si-Cat phase isotypic with a-Leboite (Fe1-xSi2). Mater Sci Eng A 104:249–254CrossRefGoogle Scholar
  10. 10.
    Margarito F, Martins J P, Figueiredo M O, Bastos MH (1993) Kinetics of acid leaching refining of an industrial Fe-Si alloy. Hydrometallurgy 34(1):1–11CrossRefGoogle Scholar
  11. 11.
    Lai H, Huang L, Lu C, Luo X (2015) Leaching behavior of impurities in Ca alloyed metallurgical grade silicon. Hydrometallurgy 156:173–181CrossRefGoogle Scholar
  12. 12.
    Ma X, Zhang J, Wang T, Li T (2009) Hydrometallurgical purification of metallurgical grade silicon. Rare Met 28(3):221–225CrossRefGoogle Scholar
  13. 13.
    Sanderson R T (1983) Polar covalence. Academic Press, New YorkGoogle Scholar
  14. 14.
    Zhang H, Wang Z, Xie K, Hu L (2013) Chemical cracking effect of aqua regia on the purification of metallurgical-grade silicon. Ind Eng Chem Res 52:7289–7296CrossRefGoogle Scholar
  15. 15.
    Sun Y, Ye Q, Guo C, Yang C (2013) Purification of metallurgical-grade silicon via acid leaching, calcination, and quenching before boron complexation. Hydrometallurgy 139(1):64–72CrossRefGoogle Scholar
  16. 16.
    Kelsall GH, Williams RA (1991) Electrochemical behavior of Ferro silicides (FexSi) in neutral and alkaline aqueous electrolytes. J Electrochem Soc 138:931–940CrossRefGoogle Scholar
  17. 17.
    Kim E, Osseo-Asare K (2012) Dissolution windows for hydrometallurgical purification of metallurgical-grade silicon to solar-grade silicon: Eh-pH diagrams for Fe silicides. Hydrometallurgy 127–128:178–186CrossRefGoogle Scholar
  18. 18.
    Ali M, UI Haq E, Karim M R, Baig W (2016) Effect of leaching with 5–6 N H2 SO 4 on the thermal kinetics of rice husk during pure silica recovery. J Adv Res 07:47–51CrossRefGoogle Scholar
  19. 19.
    Yu Z, Xie K, Xie G, Dai Y (2011) Kinetics of iron removal from metallurgical grade silicon with pressure leaching. Rare Met 30(6):688–694CrossRefGoogle Scholar
  20. 20.
    Tobergte D R, Curtis S (2013) Rate processes of extractive metallurgy. Miner Eng 53(9):1–286Google Scholar

Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Isfahan University of TechnologyIsfahanIslamic Republic of Iran

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