Silicon powder production by electrochemical reduction of SiO2 in molten LiCl–Li2O

In this paper, we reported on the electrochemical reduction of SiO2 using LiCl–Li2O molten salt as an electrolyte. Feed material, SiO2 powder, contained in a porous magnesia basket was charged into an electrolysis cell and made as a cathode. Reduction in LiCl–Li2O molten salt allowed for a much lower reaction temperature compared to the electrochemical reduction in molten CaCl2. Li metal production via electrolysis of Li2O and reduction of SiO2 took place simultaneously inside the cathode basket of an electrolysis cell. Analysis of the time-dependent changes of a phase composition showed that the reduction proceeded through Li2SiO3. This new silicon preparation technique was compared with the conventional deoxidation methods reported in the literature.