Process for producing fluoropropenes
Dehydrohalogenation processes for the preparation of fluoropropenes from corresponding halopropanes, in which the fluoropropenes have the formula CF 3 CY═CX N H P , wherein X and Y are independently hydrogen or a halogen selected from fluorine, chlorine, bromine and iodine; and N and P are independently integers equal to 0, 1 or 2, provided that (N+P)=2.
1. A process for the manufacture of 1,3,3,3-tetrafluoropropene comprising:
providing 1-chloro-1,3,3,3-tetrafluoropropane and 1,1,1,3,3-pentafluoropropane in a reactant stream; and
reacting said 1-chloro-1,3,3,3-tetrafluoropropane and said 1,1,1,3,3-pentafluoropropane under conditions sufficient to form a reaction product which comprises 1,3,3,3-tetrafluoropropene.
2. The process of claim 1 wherein 1-chloro-1,3,3,3-tetrafluoropropane is dehydrochlorinated to form a reaction product which comprises 1,3,3,3-tetrafluoropropene.
3. The process of claim 1 wherein 1,1,1,3,3-pentafluoropropane is dehydrofluorinated to form a reaction product which comprises 1,3,3,3-tetrafluoropropene.
4. The process of claim 1 which is conducted at a temperature of from about 30° C. to about 400° C.
5. The process of claim 1 which is conducted at a temperature of from about 50° C. to about 350° C.
6. The process of claim 1 which is conducted at a temperature of from about 75° C. to about 300° C.
7. The process of claim 1 which is conducted at atmospheric pressure or under vacuum.
8. The process of claim 1 which is conducted a superatmospheric pressure.
9. The process of claim 1 , wherein said reacting step comprises reacting in the presence of a fluorinated transition metal oxide catalyst.
10. The process of claim 9 wherein said fluorinated transition metal oxide is fluorinated chromium (III) oxide.
11. The process of claim 10 wherein said fluorinated chromium (III) oxide is formed by fluorinating chromium (III) oxide with HF.
12. The process of claim 1 wherein the 1-chloro-1,3,3,3-tetrafluoropropane and/or 1,1,1,3,3-pentafluoropropane are previously prepared by fluorinating 1,1,1,3,3-pentachloropropane with hydrogen fluoride in the vapor phase in the presence of a fluorination catalyst.
13. The process of claim 12 wherein said fluorination catalyst is selected from the group consisting of transition metal halides, Group IVb metal halides, Group Vb metal halides and combinations thereof on activated carbon or fluorinated alumina.
14. The process of claim 13 wherein said fluorination catalyst is selected from the group consisting of SbCl 5 , SbCl 3 , SbF 5 , TaCl 5 , SnCl 4 , NbCl 5 , TiCl 4 , MoCl 5 , Cr 2 O 3 , Cr 2 O 3 /Al 2 O 3 , Cr 2 O 3 /AlF 3 , Cr 2 O 3 /carbon, CoCl 2 /Cr 2 O 3 /Al 2 O 3 , NiCl 2 /Cr 2 O 3 /Al 2 O 3 , CoCl 2 /AlF 3 , NiCl 2 /AlF 3 and combinations thereof.
15. The process of claim 13 wherein said fluorination catalyst is selected from the group consisting of Cr 2 O 3 , Cr 2 O 3 /carbon, Cr 2 O 3 /AlF 3 , CoCl 2 /AlF 3 , NiCl 2 /AlF 3 and combinations thereof.
16. The process of claim 13 wherein said fluorination catalyst comprises SbCl 3 or SbCl 5 supported on activated carbon.
17. The process of claim 12 wherein the fluorinating is conducted at a temperature of from about 100° C. to about 350° C.
18. The process of claim 12 wherein the fluorinating is conducted at atmospheric pressure or under vacuum.
19. The process of claim 12 wherein the fluorinating is conducted at superatmospheric pressure.
20. The process of claim 12 wherein the mole ratio of hydrogen fluoride to 1,1,1,3,3-pentachloropropane is from about 2:1 to about 100:1.
21. The process of claim 12 further comprising feeding chlorine to the fluorinating reaction to keep the fluorination catalyst active.
22. The process of claim 1 wherein the 1-chloro-1,3,3,3-tetrafluoropropane and/or 1,1,1,3,3-pentafluoropropane are previously prepared by fluorinating 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a liquid phase in the presence of a fluorination catalyst.
23. The process of claim 22 wherein said fluorination catalyst is selected from the group consisting of transition metal halides, Group IVb metal halides, Group Vb metal halides and combinations thereof.
24. The process of claim 23 wherein said fluorination catalyst is selected from the group consisting of SbCl 5 , SbCl 3 , SbF 5 , TaCl 5 , SnCl 4 , NbCl 5 , TiCl 4 , MoCl 5 , and combinations thereof.
25. The process of claim 23 wherein said fluorination catalyst is selected from the group consisting of SbCl 5 , SbCl 3 and combinations thereof.
26. The process of claim 22 wherein the fluorinating is conducted at a temperature of from about 60° C. to about 180° C.
27. The process of claim 22 wherein the fluorinating is conducted at a pressure of from about 50 psig and 400 psig.
28. The process of claim 22 wherein the mole ratio of hydrogen fluoride to 1,1,1,3,3-pentachloropropane is from about 2:1 to about 100:1.
29. The process of claim 22 further comprising feeding chlorine to the fluorinating reaction to keep the fluorination catalyst active.
30. The process of claim 1 wherein said reacting step comprising thermally decomposing said 1-chloro-1,3,3,3-tetrafluoropropane and said 1,1,1,3,3-pentafluoropropane to form a reaction product which comprises 1,3,3,3-tetrafluoropropene.
31. The process of claim 1 wherein said reacting step is conducted in the substantial absence of catalyst.
32. The process of claim 1 wherein said reacting step is conducted in a solution of at least one alkali or alkaline earth metal hydroxide in a non-aqueous, non-alcohol solvent.