Patent ID: 7371309

Claim:
A process for separating difluoromethane (HFC-32) from a first mixture consisting essentially of difluoromethane (HFC-32) and dichlorodifluoromethane (CFC-12), comprising the steps of: contacting the first mixture with a hydrocarbon extractive agent having from 5 to 9 carbon atoms and having a normal boiling point greater than about 30° C. and less than about 155° C. to form a second mixture; separating difluoromethane (HFC-32) from dichlorodifluoromethane (CFC-12) by distilling the second mixture in an extractive distillation zone; and recovering difluoromethane (HFC-32) substantially free of dichlorodifluoromethane (CFC-12) as an overhead product, and recovering said extractive agent and dichlorodifluoromethane (CFC-12) from the bottom of said extractive distillation zone.