Patent ID: 8404906

Claim:
A process for producing 1,2,3,4-tetrachlorohexafluorobutane comprising: a step (1) of allowing 1,2,3,4-tetrachlorobutane to react with a fluorine gas to produce a reaction product comprising 1,2,3,4-tetrachlorohexafluorobutane and hydrogen-containing compounds as an impurity, and a step (2) of introducing the reaction product into single or plural distillation columns and distilling to separate the hydrogen containing compounds from the reaction product and thereby preparing purified 1,2,3,4-tetrachlorohexafluorobutane, wherein the distillation columns comprise a first distillation column having a theoretical plate number of 15 or more and a second distillation column having a theoretical plate number of 25 or more, and the step (2) comprises a step (2a) of introducing the reaction product into the first distillation column and distilling and thereby separating the hydrogen-containing compounds from the reaction product to prepare a distillate mainly containing 1,2,3,4-tetrachlorohexafluorobutane from the top of the first distillation column, and a step (2b) of introducing the distillate into the second distillation column and distilling to prepare purified 1,2,3,4-tetrachlorohexafluorobutane from the bottom of the second distillation column.