METHOD OF TETRAFLUOROETHYLENE SYNTHESIS Russian patent published in 1995 - IPC

FIELD: organic chemistry. SUBSTANCE: tetrafluoroethylene is synthesized by pyrolysis of difluorochloromethane followed by removal of acid impurities and rectification isolation of the end product, and also fraction of difluorochloromethane and hexafluoropropylene forming azeotropic mixture with difluorochloromethane. Difluorochloromethane is separated and recovered to pyrolysis. Separation of difluorochloromethane is carried out by countecurrent treatment with water in order to simplify this method. Water is taken at concentration 100-200 mole per 1 mole difluorochloromethane at 5-25 C under pressure 3-7 atm. Refined difluorochloromethane is isolated by pressure decrease over aqueous solution up to atmospheric value. Gases nonsorbed at water treatment were subjected for rectification, and hexafluoropropylene is isolated. EFFECT: improved method of synthesis. 2 cl, 1 tbl