Methods to separate halogentated olefins from 2-chloro-1,1,1,2-tetrafluoropropane using a solid adsorbent
View Patent ↗The present invention provides a method for separating halocarbons. In particular, the invention provides a method for separating halogenated olefin impurities from 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) using a solid adsorbent, particularly activated carbon. More particularly the invention pertains to a method for separating 2-chloro-3,3,3-trifluoro-propene (HCFO-1233xf) from HCFC-244bb, which are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).
1. A method for separating halogenated olefin impurities from 2-chloro-1,1,1,2-tetrafluoropropane consisting of contacting the impure 2-chloro-1,1,1,2-trtrafluoropropane with a solid adsorbent that adsorbs the halogenated olefin impurities from the 2-chloro-1,1,1,2-tetrafluoropropane.
2. The method of claim 1 , wherein the solid adsorbent comprises activated carbon.
3. The method of claim 2 , wherein the activated carbon has a minimum Iodine Number of 900.
4. The method of claim 2 , wherein the activated carbon has a minimum Iodine Number of 1000.
5. The method of claim 2 , wherein the activated carbon has a minimum Iodine Number of 1100.
6. The method of claim 2 , wherein the activated carbon has a minimum Iodine Number of 1200.
7. The method of claim 2 , wherein the activated carbon is a coconut shell based carbon.
8. The method of claim 2 , wherein the activated carbon is a coal based carbon.
9. The method of claim 2 , wherein the halogenated olefin impurities comprise 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf).
10. A method for separating halogenated olefin impurities from a crude mixture with 2-chloro-1,1,1,2-tetrafluoropropane consisting essentially of contacting the crude mixture with a solid adsorbent that adsorbs the halogenated olefin impurities for a sufficient time to adsorb the halogenated olefin impurities from the crude mixture and wherein the halogenated olefin impurities comprise HCFO-1224 isomers.
11. The method of claim 10 , wherein the solid adsorbent comprises activated carbon.
12. The method of claim 11 , wherein the activated carbon has a minimum Iodine Number of 900.
13. The method of claim 11 , wherein the activated carbon has a minimum Iodine Number of 1000.
14. The method of claim 11 , wherein the activated carbon has a minimum Iodine Number of 1100.
15. The method of claim 11 , wherein the activated carbon has a minimum Iodine Number of 1200.
16. The method of claim 11 , wherein the activated carbon is a coconut shell based carbon.
17. The method of claim 11 , wherein the activated carbon is a coal based carbon.
18. The method of claim 11 , wherein the crude mixture is passed over the solid adsorbent for a period of time sufficient to adsorb the impurities.
19. The method of claim 11 , wherein the solid adsorbent is regenerated after use to remove the impurities adsorbed thereon.
20. The method of claim 11 , wherein the solid adsorbent is added to the mixture for a period of time sufficient to adsorb the impurities.