| abstract |
PCT No. PCT/JP93/00455 Sec. 371 Date Dec. 9, 1993 Sec. 102(e) Date Dec. 9, 1993 PCT Filed Apr. 9, 1993 PCT Pub. No. WO93/21140 PCT Pub. Date Oct. 28, 1993.Hydrogen fluoride is effectively removed from a mixture of hydrogen fluoride, dichloromethane, chlorofluoromethane and/or difluoromethane by distilling the mixture so that two-component azeotropic mixtures of hydrogen fluoride and dichloromethane, hydrogen fluoride and chlorofluoromethane and hydrogen fluoride and difluoromethane are removed, or by liquid-separating the mixture into an upper liquid phase rich in hydrogen fluoride and a lower liquid phase not rich in hydrogen fluoride before each liquid phase is distilled as described above. |