Disclosed is a process for producing hexafluoro-2-butyne comprising, reacting HCFC-336 with an aqueous solution of an alkali metal hydroxide in the presence of a quaternary alkylammonium salt which comprises at least one alkyl group of at least 8 carbons, and recovering the hexafluoro-2-butyne, wherein the conversion of dichloro-1,1,1,4,4,4-hexafluorobutane is at least 50% per hour. Also disclosed is a process for producing hexafluoro-2-butyne comprising, reacting HCFC-336 with an aqueous solution of an alkali metal hydroxide in the presence of a quaternary alkylammonium salt having alkyl groups of from four to ten carbon atoms, and mixtures thereof, and a non-ionic surfactant, and recovering the hexafluoro-2-butyne, and wherein the conversion of dichloro-1,1,1,4,4,4-hexafluorobutane to hexafluoro-2-butyne is at least 20% per hour.