METHOD OF PRODUCING SILICON Russian patent published in 2011 - IPC C01B33/33 C01B33/08 

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. Silicon tetrafluoride and sodium fluoride are separated via thermal dissociation of sodium silicofluoride at temperature higher than 923 K, and silicon is then reduced from silicon tetrafluoride upon contact with sodium. Separation and reduction are carried out while insulated from the external medium and from each other. Before separating silicon tetrafluoride, water, nitrogen and/or hydrocarbons are removed via vacuum stripping at temperature 923±20 K. Residual sodium is removed via vacuum distillation at temperature higher than 623 K, but lower than the melting point of sodium fluoride.

EFFECT: invention enables to obtain silicon with less than 10^-4 pts wt content of impurities.

2 cl, 4 dwg, 1 tbl, 1 ex