METHOD FOR PRODUCING SILICON TETRAFLUORIDE AND APPARTUS USED THEREFOR

摘要

PURPOSE: A silicon tetrafluoride preparing method for economically producing plenty of silicon tetrafluoride and an apparatus for preparing the same are provided to obtain silicon tetrafluride through a continuous process by reacting a silicon dioxide containing material and hydrogen fluoride under sulfuric acid. CONSTITUTION: A silicon tetrafluoride preparing method includes the following: a silicon dioxide containing material and hydrogen fluoride are reacted under sulfuric acid in a first reactor(6); at least part of hydrogen fluoride containing sulfuric acid is transferred to a second reactor(12); a silicon dioxide containing material is further introduced into the second reactor and is reacted with hydrogen fluoride; and silicon tetrafluoride and sulfuric acid without hydrogen fluoride or with a few amount of the hydrogen fluoride. The sulfuric acid is concentrated to be reused.