Patent ID: 8877017

Claim:
A method for separating hexafluoropropylene oxide from hexafluoropropylene, which comprises subjecting a mixture including hexafluoropropylene oxide and hexafluoropropylene to an extractive distillation operation using, as a solvent, at least one of a fluorine-containing saturated compound selected from the group consisting of 1,1,1,3,3-pentafluoropropane; 1,1,1,3,3-pentafluorobutane; 1,1,1,2,2,3,4,5,5,5-decafluoropentane; and 1,1,2,2,3,3,4-heptafluorocyclopentane, and thereby separating the mixture into a first fraction including hexafluoropropylene oxide and a second fraction including hexafluoropropylene and the solvent.