The Separation of Refined Silicon by Gas Pressure Filtration in Solvent Refining Process

  • Tianyang Li
  • Lei Guo
  • Zhe Wang
  • Zhancheng GuoEmail author
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


The separation of refined silicon by gas pressure filtration combined with solvent refining was studied. The purified silicon grains were separated by gas pressure filtration under a pressure differential of 0.2 MPa. In all of the systems, Al–40%Si, Sn–40%Si, Cu–40%Si, and Fe–80%Si, the effect of separation temperature (T) on separation efficiency was evaluated. In Al–40%Si alloy, the silicon content in separated silicon was 91.3 wt% and the recovery rate of silicon was 97.6%, at T = 600 °C. In Sn–40%Si alloy, almost all of the silicon was retained, and the silicon content in separated silicon was 79.4 wt% at T = 600 °C. For Cu–40%Si alloy and Fe–80%Si alloy, the silicon content in separated silicon was over 75 wt% under high superheat. With efficient removal of impurities, the combination of gas pressure filtration and solvent refining is a promising method.


Filtration Gas pressure Silicon Solvent refining 



This work was supported by the National Natural Science Foundations of China (Grant No.51804030) and the Key Projects of the State Key Research and Development Plan of China (2016YFB0601304).


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© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.State Key Laboratory of Advanced MetallurgyUniversity of Science and Technology BeijingBeijingChina

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