Patent ID: 8481793

Claim:
A method for the production of 2,3,3,3-tetrafluoropropene which comprises (i) continuously reacting 2-chloro-3,3,3-trifluoropropene with hydrogen fluoride, in a liquid phase reaction, in the presence of a liquid phase fluorination catalyst to produce a composition comprising unreacted HF, unreacted 2-chloro-3,3,3-trifluoropropene, and 2-chloro-1,1,1,2-tetrafluoropropane; and then (ii) isolating an azeotrope or azeotrope-like composition of 2-chloro-1,1,1,2-tetrafluoropropane and 2-chloro-3,3,3-trifluoropropene; and then (iii) isolating 2-chloro-1,1,1,2-tetrafluoropropane from the azeotrope or azeotrope-like composition by cooling the azeotrope or azeotrope-like composition at or below the freezing point of 2-chloro-1,1,1,2-tetrafluoropropane but above the freezing point of 2-chloro-3,3,3-trifluoropropene; and then (iv) dehydrochlorinating the isolated 2-chloro-1,1,1,2-tetrafluoropropane under conditions effective to produce 2,3,3,3-tetrafluoropropene; and (v) optionally, recycling the isolated 2-chloro-3,3,3-trifluoropropene back to the reaction of step (i).