SILICON TETRAFLUORIDE SYNTHESIS METHOD AND DEVICE FOR REALISING SAID METHOD Russian patent published in 2010 - IPC C01B33/107 

FIELD: chemistry.

SUBSTANCE: invention can be used in making optical fibre, semiconductors and solar cells. Starting materials containing silicon dioxide react with a solution of hydrofluoric and hydrofluosilicic acid to obtain an aqueous solution of fluorosilicic acid (H₂Si₂F₁₀) in a reactor pot 3. The aqueous solution of fluorosilicic acid is reacted with sulphuric acid to obtain silicon tetrafluoride in a packed column 19. A fraction of sulphuric acid containing hydrofluoric acid - a by-product from the silicon tetrafluoride synthesis step undergoes steam stripping to obtain sulphuric acid in a steaming-stripping column 28. The obtained sulphuric acid is concentrated in an evaporator 32 and returned to the silicon tetrafluoride synthesis step for recycling.

EFFECT: invention reduces expenses and wastes during production of silicon tetrafluoride.

11 cl, 1 dwg, 1 tbl, 1 ex