Method for co-producing 2,3,3,3-tetrafluoropropene and trans-1,3,3,3-tetrafluoropropene

摘要

Disclosed is a method for co-producing 2,3,3,3-tetrafluoropropene and trans-1,3,3,3-tetrafluoropropene, comprising the following steps: preheating a mixture of 1,1,1,2,2-pentachloropropane and 1,1,1,3,3-pentachloropropane together with anhydrous hydrogen fluoride and simultaneously introducing into a first reactor to react in the presence of a catalyst La₂O₃—Cr₂O₃ to obtain a first reactor product; directly introducing the first reactor product into a second reactor without separation, and carrying out a catalytic fluorination reaction in the presence of a catalyst Ga₂O₃—Y₂O₃—Cr₂O₃ to obtain a second reactor product; and separating the second reactor product to obtain the products of 2,3,3,3-tetrafluoropropene and trans-1,3,3,3-tetrafluoropropene. The invention has such advantages that the process is simple and less equipment investment is required; used catalysts have good activity, high selectivity and long total life; and the ratio of the two products can be flexibly adjusted according to market demands.