METHOD FOR SEPARATING HFC-32 AND HFC-125

摘要

PROBLEM TO BE SOLVED: To provide a method for separating difluoromethane (HFC-32) and pentafluoroethane (HFC-125) from a mixture comprising both of them using an extractant comprising methylene chloride. SOLUTION: The method comprises the steps of: adding the extractant to the mixture to form a second mixture; separating HFC-32 and HFC-125 in the second mixture by extractively distilling the second mixture in an extractive distillation zone of a distillation column and thereby recovering HFC-125 as an overhead product of the column and HFC-32 from the column bottom. COPYRIGHT: (C)2007,JPO&INPIT