AZEOTROPIC MIXTURE AND HYDROGEN FLUORIDE ISOLATION METHODS Russian patent published in 1998 - IPC

FIELD: industrial organic synthesis. SUBSTANCE: hydrogen fluoride is efficiently removed from mixture consisting of hydrogen fluoride, dichloromethane, chlorofluoromethane, and/or difluoromethane via (i) distillation of mixture to remove two-component hydrogen fluoride- dichloromethane, hydrogen fluoride-hlorofluoromethane, and hydrogen fluoride-difluoromethane azeotropic mixtures or (ii) separating mixture into upper liquid hydrogen fluoride-enriched phase and lower liquid hydrogen fluoride-depleted phase followed by distillation of corresponding phases as described in (i). EFFECT: simplified method and increased its efficiency. 7 cl, 2 dwg, 7 tbl