Process for drying HCFO-1233zd
The present disclosure provides separation processes that use azeotropic or azeotropic-like compositions of 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd) that allow for improved recovery rates of 1-chloro-3,3,3-trifluoropropene during or after manufacturing processes. Such recovery or separation processes can utilize the unique properties of azeotropic or azeotropic-like composition with various combinations of separation techniques (e.g., distillation and decanting) that yield highly pure compositions of 1-chloro-3,3,3-trifluoropropene and simultaneously offer high yields of 1-chloro-3,3,3-trifluoropropene. Such highly pure compositions of 1-chloro-3,3,3-trifluoropropene may find useful applications in polymer technology as monomers or comonomers.
1. A method for recovering 1-chloro-3,3,3-trifluoropropene comprising,
forming an azeotropic or azeotrope-like composition comprising 1-chloro-3,3,3-trifluoropropene and water;
conveying the formed azeotropic or azeotrope-like composition into a separator; and
recovering an organic layer comprising 1-chloro-3,3,3-trifluoropropene.
2. The method of claim 1 , wherein the composition comprises from about 0.05 wt. % to about 30 wt. % water and from about 70 wt. % to about 99.95 wt. % 1-chloro-3,3,3-trifluoropropene, based on the combined weight of water and 1-chloro-3,3,3-trifluoropropene.
3. The method of claim 1 , wherein the composition has a boiling point of about 17.4° C.±1° C. at a pressure of about 14.7 psia.
4. The method of claim 1 , wherein the recovering step further comprises decanting off a water layer.
5. The method of claim 1 , further comprising the additional step of returning the organic layer to a distillation column.
6. The method of claim 5 , further comprising the additional step of separating water in the organic layer from 1-chloro-3,3,3-trifluoropropene with distillation.
7. The method of claim 1 , wherein the azeotropic or azeotrope-like composition consists essentially of 1-chloro-3,3,3-trifluoropropene and water.
8. The method of claim 7 , wherein the azeotropic or azeotrope-like composition consists of 1-chloro-3,3,3-trifluoropropene and water.
9. A method comprising:
providing a mixture of 1-chloro-3,3,3-trifluoropropene and water;
allowing the mixture to separate into an organic layer including mostly 1-chloro-3,3,3-trifluoropropene and an aqueous layer;
decanting a portion of the aqueous layer from the mixture;
conveying the organic layer to a distillation column;
forming an azeotropic mixture of 1-chloro-3,3,3-trifluoropropene and water in the distillation column;
removing the azeotropic mixture from the distillation column as an overhead stream; and
removing substantially pure 1-chloro-3,3,3-trifluoropropene from the bottoms of the distillation column.
10. The method of claim 9 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains less than about 100 ppm of water by weight.
11. The method of claim 10 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains less than about 40 ppm of water by weight.
12. The method of claim 11 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains less than about 20 ppm of water by weight.
13. The method of claim 9 , wherein the azeotropic mixture comprises from about 0.05 wt. % to about 30 wt. % water and from about 70 wt. % to about 99.95 wt. % 1-chloro-3,3,3-trifluoropropene, based on the combined weight of water and 1-chloro-3,3,3-trifluoropropene.
14. The method of claim 10 , wherein the azeotropic mixture comprises from about 0.05 wt. % to about 14 wt. % water and from about 86 wt. % to about 99.95 wt. % 1-chloro-3,3,3-trifluoropropene, based on the combined weight of water and 1-chloro-3,3,3-trifluoropropene.
15. The method of claim 9 , wherein the azeotropic mixture has a boiling point of about 17.4° C.±1° C. at a pressure of about 14.7 psia.
16. The method of claim 11 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains between about 10 ppm of water by weight and about 40 ppm of water by weight.
17. The method of claim 16 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains between about 10 ppm of water by weight and about 30 ppm of water by weight.
18. The method of claim 17 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains between about 15 ppm of water by weight and about 20 ppm of water by weight.
19. The method of claim 16 , wherein the substantially pure 1-chloro-3,3,3-trifluoropropene removed from the distillation column contains between about 11 ppm of water by weight and about 20 ppm of water by weight.
20. The method of claim 9 , wherein the azeotropic mixture consists essentially of 1-chloro-3,3,3-trifluoropropene and water.