The application discloses a
separation method of tetrafluoropropylene and tetrafluoroethane mixture, mainly comprising the following steps: taking the tetrafluoropropylene and tetrafluoroethane mixture as raw materials, adding
ionic liquid in an extractive rectification
tower, and performing extractive rectification on the raw materials, wherein the cation of the
ionic liquid has the structure of formula (I), and the anion is one of
perchlorate ion [ClO4] or fluorosulfonylimide [FSI]
ion. In formula (I), R and R' are respectively selected from C1-C4
alkyl. The specified
ionic liquid is added in the extractive rectification
tower, high-efficiency separation of the tetrafluoropropylene and tetrafluoroethane mixture is realized, high-purity tetrafluoropropylene and tetrafluoroethane can be obtained, the
mass purity of the tetrafluoropropylene and tetrafluoroethane products can be as high as 99.6%, and compared with other ionic liquids, the ionic liquid used in the application has smaller
energy consumption in the extractive rectification
separation process under the condition of obtaining products with the same purity, and the annual economic cost is lower.