Process for producing fluoropropenes

• US 8,247,624 B2
• Filed: 09/06/2011
• Issued: 08/21/2012
• Est. Priority Date: 10/27/2003
• Status: Expired due to Term

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Merkel, Daniel C., Singh, Rajiv R., Tung, Hsueh S.
• Primary Examiner(s): WITHERSPOON, SIKARL A
• Application Number:
  US13/226,019
• Publication Number:
  US 20120053370A1
• Time in Patent Office: 350 Days
• Field of Search: 570/156, 570/157, 570/167, 570/168
• US Class Current: 570/156
• CPC Class Codes: C07C 17/206 the other compound being HX
• CPC Class Codes: C07C 17/25 by splitting-off hydrogen halides from halogenated hydrocarbons
• CPC Class Codes: C07C 19/08 containing fluorine
• CPC Class Codes: C07C 19/10 and chlorine
• CPC Class Codes: C07C 21/18 containing fluorine

Abstract

Dehydrohalogenation processes for the preparation of fluoropropenes from corresponding halopropanes, in which the fluoropropenes have the formula CF₃CY═CX_NH_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.

Claims

1. A dehydrohalogenation process for the preparation of fluoropropenes of the formula CF₃CY═

CX_NH_p, wherein X and Y are independently hydrogen or a halogen selected from the group consisting of fluorine, chlorine, bromine and iodine; and

N and P are independently integers equal to 0, 1, or 2, provided that (N+P)=2;

comprising reacting a halopropane of the formula;

CF₃C(YR₁)C(X_NH_PR₂)

wherein R₁, R₂, X and Y are independently hydrogen or a halogen selected from the group consisting of fluorine, chlorine, bromine and iodine, provided that at least one of R₁, R₂, X and Y is a halogen and there is at least one hydrogen and one halogen on adjacent carbon atoms;

with a caustic solution of at least one alkali metal or alkaline earth metal hydroxide in a non-aqueous, non-alcohol solvent for said alkali metal or alkaline earth metal hydroxide that is essentially miscible with said halopropane.

2. The process of claim 1 wherein the reactant comprises 1-chloro-1,3,3,3-tetrafluoropropane.

3. The process of claim 1 wherein the reactant comprises 1,1,1,3,3-pentafluoropropane.

4. The process of claim 1 wherein the reactant comprises both 1-chloro-1,3,3,3-tetrafluoropropane and 1,1,1,3,3-pentafluoropropane.

5. The process of claim 4 wherein said dehydrochlorination of 1-chloro-1,3,3,3-tetrafluoropropane and said dehydrofluorination of 1,1,1,3,3-pentafluoropropane are conducted simultaneously in the same reactor.

6. The process of claim 1 wherein said caustic solution comprises LiOH, NaOH, KOH, CaO, Ca(OH)₂, CaCO₃, lime stone or combinations thereof.

7. The process of claim 1, wherein said caustic solution solvent is selected from the group consisting of nitriles, ethers, esters, amides, ketones, sulfoxides, phosphates, carboxylates, and combinations of two or more of these.

8. The process of claim 1, wherein said caustic solution solvent comprises acetonitrile.

9. The process of claim 1, wherein said caustic solution solvent comprises diethyl ether.

10. The process of claim 1, wherein said caustic solution solvent comprises tetrahydrofuran.

11. The process of claim 1, wherein said caustic solution solvent comprises perfluorotetrahydrofuran.

12. The process of claim 1, wherein said caustic solution solvent comprises methyl acetate.

13. The process of claim 1, wherein said caustic solution solvent comprises ethyl acetate.

14. The process of claim 1 wherein the reaction is conducted at a temperature of from about 20°

C. to about 150°

C.

15. The process of claim 1 wherein the reaction is conducted at atmospheric pressure or under vacuum.

16. The process or claim 1 wherein the reaction is conducted at superatmospheric pressure.

17. The process of claim 1 wherein the caustic strength of said caustic solution is from about 2 wt % to about 100 wt %.

18. The process of claim 1, wherein the molar ratio of caustic to halopropane is about 1:

1 to about 20;

1.

19. A dehydrohalogenation process for the preparation of fluoropropenes of the formula CF₃CY═

CX_NH_p, wherein X and Y are independently hydrogen or a halogen selected from the group consisting of fluorine, chlorine, bromine and iodine, and N and P are independently integers equal to 0, 1 or 2, provided that (N+P)=2;

comprising heating to a temperature at which dehydrohalogenation by thermal decomposition occurs, a halopropene of the formula;

CF₃C(YR₁)C(X_NH_PR₂)

wherein R₁, R₂, X and Y are independently hydrogen or a halogen selected from the group consisting of fluorine, chlorine, bromine and iodine, provided that least one of R₁, R₂, X and Y is a halogen and there is at least one hydrogen and one halogen on adjacent carbon atoms.

20. The process of claim 19 wherein the reactant comprises 1-chloro-1,3,3,3-tetrafluoropropane.

21. The process of claim 19 wherein the reactant comprises 1,1,1,3,3-pentafluoropropane.

22. The process of claim 19 wherein the reactant comprises both 1-chloro-1,3,3,3-tetrafluoropropane and 1,1,1,3,3-pentafluoropropane.

23. The process of claim 22 wherein said dehydrochlorination of 1-chloro-1,3,3,3-tetrafluoropropane and said dehydrofluorination of 1,1,1,3,3-pentafluoropropane are conducted simultaneously in the same reactor.

24. The process of claim 19 wherein the reaction is conducted at a temperature of from about 30°

C. to about 400°

C.

25. The process of claim 19 wherein the reaction is conducted at a temperature of from about 50°

C. to about 350°

C.

26. The process of claim 19 wherein the reaction is conducted at a temperature of from about 75°

C. to about 300°

C.

27. The process of claim 19 wherein the reaction is conducted at atmospheric pressure or under vacuum.

28. The process or claim 19 wherein the reaction is conducted at superatmospheric pressure.

29. The process of claim 19 wherein said decomposing is conducted in the presence of a transition metal halide catalyst.

30. The process of claim 29 wherein said transition metal is selected from the group consisting of iron, nickel, cobalt, and combinations thereof.

31. The process of claim 29 wherein the catalyst is supported or bulk transition metal halides.

32. The process of claim 29 wherein said catalyst comprises supported or bulk FeCl₂, FeCl₃, NiCl₂ or CoCl₂.