Process for removing silicon tetrafluoride from gaseous boron trifluoride

摘要

Silicon tetrafluoride is removed from gaseous boron trifluoride by treating the gas in a first stage at temperatures of from 10 to 60@C with a solution containing from 55 to 70% by weight of dissolved boron trifluoride. From this stage there is drawn off an exit gas which comprises practically pure silicon tetrafluoride and also a boron trifluoride-enriched solution from which boron trifluoride is desorbed at temperatures of from 90 to 200@C.