Process for drying HCFO-1233zd

Patent metadata

Field	Value
Publication number	US-9926244-B2
Application number	US-201615368027-A
Country	US
Kind code	B2
Filing date	Dec 2, 2016
Priority date	Oct 28, 2008
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

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.

First claim

What is claimed is:

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.

Assignees

• Honeywell Int Inc

Inventors

• Chiu Yuon
• Cottrell Stephen A
• Pham Hang T
• Cerri Gustavo

Classifications

• C07C17/389

  by adsorption on solids · CPC title

• C07C21/18

  containing fluorine · CPC title

• C07C17/383 Primary

  by distillation · CPC title

• C07C17/38 Primary

  Separation; Purification; Stabilisation; Use of additives · CPC title