Process for producing trifluoroiodomethane (CF3I) from trifluoroacetic anhydride (TFAA)
The present disclosure relates to a method for producing trifluoroiodomethane (CF 3 I) from iodine (I 2 ) and trifluoroacetic anhydride (TFAA) under photochemical conditions using ultraviolet (UV) light.
1. A method for making trifluoroiodomethane (CF 3 I) comprising:
combining iodine (I 2 ) and trifluoroacetic anhydride (TFAA); and
irradiating the mixture with ultraviolet (UV) light to produce a product stream.
2. The method of claim 1 , wherein the combining and irradiating steps are conducted continuously.
3. The method of claim 1 , wherein the ratio of iodine (I 2 ) to trifluoroacetic anhydride (TFAA) is from about 0.1:1 to about 100:1.
4. The method of claim 3 , wherein the ratio of iodine (I 2 ) to trifluoroacetic anhydride (TFAA) is from about 10:1 to about 20:1.
5. The method of claim 1 , wherein the ultraviolet (UV) light is broad spectrum ultraviolet (UV) light.
6. The method of claim 5 , wherein the broad spectrum ultraviolet light (UV) is 200 nm-400 nm ultraviolet (UV) light.
7. The method of claim 1 , wherein the ultraviolet (UV) light is single wavelength ultraviolet (UV) light.
8. The method of claim 7 , wherein the ultraviolet (UV) light is 254 nm ultraviolet (UV) light.
9. The method of claim 1 , wherein the irradiating step is conducted with the iodine (I 2 ) and trifluoroacetic anhydride (TFAA) in the liquid phase.
10. The method of claim 1 , further comprising, prior to the combining step, dissolving the iodine (I 2 ) in a solvent.
11. The method of claim 10 , wherein the solvent is chosen from the group consisting of mesitylene, toluene, and xylenes.
12. The method of claim 1 , further comprising purifying the product stream.
13. The method of claim 1 , wherein the product stream may be passed through two or more cold traps.
14. The method of claim 13 , wherein the product stream may be passed through a first cold trap at 0° C.
15. The method of claim 13 , wherein the product stream may be passed through a second cold trap at −78° C.
16. The method of claim 1 , wherein the irradiating step is conducted with the iodine (I 2 ) and the trifluoroacetic anhydride (TFAA) in the gas phase.
17. The method of claim 16 , wherein the product stream may be passed through two or more cold traps.
18. The method of claim 17 , wherein the product stream may be passed through a first cold trap at 0° C.
19. The method of claim 17 , wherein the product stream may be passed through a second cold trap at −78° C.
20. The method of claim 1 , wherein the method achieves a conversion of at least 75%, based on the initial amount of trifluoroacetic anhydride (TFAA).