Disclosed is a process for making hexafluoro-2-butyne comprising the steps of: (a) providing a composition comprising CF3CX═CXCF3, where X=halogen; and (b) treating CF3CX═CXCF3 with a dehalogenation catalyst in the presence of a halogen acceptor compound Y, where Y is not hydrogen. The halogen acceptor compound Y is a material capable of being halogenated, preferably a compound having a multiple bond, such as an alkyne, alkene, allene, or carbon monoxide. Another suitable material capable of being halogenated is a cyclopropane. A catalyst effectively transfers halogen from CF3CX═CXCF3 to the halogen acceptor compound. Since Y is not hydrogen, the formation of CF3CX═CHCF3 is greatly reduced or eliminated.