Patent ID: 8975456
Filing Date: 2015-03-10
Classification: C07C

Abstract:
1. A method for purifying 2,3,3,3-tetrafluoropropene comprising the steps of: (1) cooling a liquid mixture containing 2,3,3,3-tetrafluoropropene and hydrogen fluoride to separate the liquid mixture into an upper liquid phase having a high hydrogen fluoride concentration and a lower liquid phase having a high 2,3,3,3-tetrafluoropropene concentration, wherein the temperature to cool the liquid mixture containing 2,3,3,3-tetrafluoropropene and hydrogen fluoride in step (1) is −5° C. or below; and (2) subjecting the lower liquid phase obtained in step (1) to a distillation operation and withdrawing a mixture containing 2,3,3,3-tetrafluoropropene and hydrogen fluoride from a top of a distillation column, thereby obtaining 2,3,3,3-tetrafluoropropene that does not substantially contain hydrogen fluoride from a bottom of the distillation column.