titleOfInvention |
Process for the preparation of 1,1,1,3,3,3-hexafluoropropane and at least one of 1,1,1,2,3,3-hexafluoropropane and 1,1,1,2,3,3,3-heptafluoropropane |
abstract |
A process is disclosed for the manufacture of 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) and at least one 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) and 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea). The process involves (a) reacting HF, Cl2, and at least one halopropene of the formula CX3CCl=CX2 (where each X is independently F or Cl) to produce a product including both CF3CCl2CF3 and CF3CClFCClF2; (b) reacting CF3CCl2CF3 and CF3CClFCClF2 produced in (a) with hydrogen to produce a product comprising CF3CH2CF3 and at least one compound selected from the group consisting of CHF2CHFCF3, and CF3CHFCF3; and (c) recovering from the product produced in (b), CF3CH2CF3 and at least one compound selected from the group consisting of CHF2CHFCF3 and CF3CHFCF3. In (a), the CF3CCl2CF3 and CF3CClFCClF2 are produced in the presence of a chlorofluorination catalyst including a ZnCr2O4/crystalline α-chromium oxide composition, a ZnCr2O4/crystalline α-chromium oxide composition which has been treated with a fluorinating agent, a zinc halide/α-chromium oxide composition and/or a zinc halide/α-chromium oxide composition which has been treated with a fluorinating agent. |