Processes for selective dehydrohalogenation of halogenated alkanes
View Patent ↗Disclosed are processes for producing halogenated olefins, and preferably tetrafluorinated propene(s), from one or more alkanes having both fluorine substituents and non-fluorine substituents, preferably with a high degree of conversion and selectivity. Preferably the process comprises the use of a catalyzed reaction in which the catalyst is selected from the group consisting of activated carbons, halogentated mono- and di-valent metal oxides, mono- and di-valent Lewis acid metal halides, zero-valent metals, and combinations of these.
1. A process for the production of a fluorinated olefin comprising CF 3 CH═CFH (HFO-1234ze) comprising dehydrohalogenation of a fluorinated and chlorinated alkane comprising CF 3 CH 2 CHClF (HCFC-244fa), in the presence of a catalyst selected from the group consisting of LiCl/C, KCl/C, MgCl2/C, NiCl2/C, LiF/C, MgF 2 /C, AlF 3 , Fe/C, Co/C, Ni/C, Cu/C and combinations of these.
2. The process of claim 1 , wherein the catalyst is a metal-based catalyst comprising Li, Na, K, Mg or a combination of these.
3. The process of claim 1 , wherein the catalyst is a metal-based catalyst component selected from the group consisting of LiCl, KCl/C and MgCl 2 /C.
4. The process of claim 1 , wherein the dehydrohalogenation is conducted in a gas phase.
5. The process of claim 1 wherein said HFO-1234ze consists essentially of a mixture of cis-HFO-1234ze and trans-HFO-1234ze.
6. The process of claim 1 wherein said catalyst is LiCl supported on by a carbon substrate.
7. The process of claim 1 wherein said dehydrohalogenation step is conducted under a reaction temperature condition of from about 300° C. to less than about 400° C.
8. The process of claim 1 wherein said dehydrohalogenation step is conducted under a reaction temperature condition of from about 325° C. to about 375° C.
9. The process of claim 1 wherein said dehydrohalogenation step is conducted under a reaction temperature condition of about 350° C.
10. The process of claim 1 wherein said dehydrohalogenation step is conducted under a reaction pressure condition of from about 5 torr to about 200 psig.
11. A process for the production of a fluorinated olefin comprising CF 3 CH═CFH (HFO-1234ze) comprising dehydrohalogenation of a fluorinated and chlorinated alkane comprising CF 3 CH 2 CHClF (HCFC-244fa), in the presence of a catalyst comprising activated carbon and one or more metal-based catalysts comprising one or more of Li, Na, K, Mg or a combination of these and wherein the metal-based catalyst component is selected from the group consisting of LiCl, KCl/C and MgCl2/C.
12. The process of claim 1 wherein said dehydrohalogenation step comprises conditions effective to convert at least about 80% by weight of said HCFC-244fa to said olefin stream comprising HFO-1234ze.
13. The process of claim 1 wherein said dehydrohalogenation step comprises conditions effective to convert at least about 90% by weight of said HCFC-244fa to said HFO-1234ze.
14. The process of claim 1 wherein said HFO-1234ze comprises trans-HFO-1234ze.
15. The process of claim 1 wherein said HFO-1234ze comprises cis-HFO-1234ze.
16. The process of claim 11 wherein said dehydrohalogenation step comprises conditions effective to convert at least about 80% by weight of said HCFC-244fa to said HFO-1234ze.
17. The process of claim 11 wherein said dehydrohalogenation step comprises conditions effective to convert at least about 90% by weight of said HCFC-244fa to said olefin stream comprising HFO-1234ze.
18. The process of claim 11 wherein said HFO-1234ze comprises trans-HFO-1234ze.
19. The process of claim 11 wherein said HFO-1234ze comprises cis-HFO-1234ze.
20. The process of claim 11 wherein said HFO-1234ze consists essentially of a mixture of cis-HFO-1234ze and trans-HFO-1234ze.
21. The process of claim 11 wherein said catalyst is LiCl supported on by a carbon substrate.
22. The process of claim 11 wherein said dehydrohalogenation step is conducted under a reaction temperature condition of from about 300° C. to less than about 400° C.
23. The process of claim 11 wherein said dehydrohalogenation step is conducted under a reaction temperature condition of from about 325° C. to about 375° C.
24. The process of claim 11 wherein said dehydrohalogenation step is conducted under a reaction temperature condition of about 350° C.
25. The process of claim 11 wherein said dehydrohalogenation step is conducted under a reaction pressure condition of from about 5 torr to about 200 psig.