Process of fluorination in liquid phase

Patent metadata

Field	Value
Publication number	US-9315431-B2
Application number	US-201414509623-A
Country	US
Kind code	B2
Filing date	Oct 8, 2014
Priority date	Mar 10, 2010
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

The present invention provides a process of fluorination in liquid phase in a solvent medium of a compound of formula (II) CX 1 X 2 =CZCX 3 X 4 X 5 , in which Z represents H, Cl or F, and each X 1 represents independently hydrogen or chlorine, given that at least one of the X 1 represents a chlorine.

First claim

The invention claimed is:

1. A process of fluorination of 1,1,2,3-tetrachloropropene comprising:
(i) contacting 1,1,2,3,-tetrachloropropene with hydrogen fluoride in a liquid phase in a solvent, under conditions sufficient to form a reaction mixture comprising 2-chloro-3,3,3-trifluoropropene, HCl, HF and 1,1,1,2-tetrafluoro-2-chloropropane, wherein the solvent is 1,2-dichloroethane, 1,2,3-trichloropropane, 1-chloro-1-fluoroethane, 1,1-difluoroethane, 1,1-dichloroethane, 1,3-dichloro-1-fluorobutane, 1,1,1,3,3-pentafluorobutane and 1,1,2-trichloro-2,2-difluoroethane, or a mixture thereof; and
(ii) separating the reaction mixture into a first stream comprising HCl, and a second stream comprising HF, 2-chloro-3,3,3-trifluoropropene and 1,1,1,2-tetrafluoro-2-chloropropane.

2. The process according to claim 1 , in which the solvent is present in a quantity for a dilution ratio from at least 20%.

3. The process according to claim 1 , in which a catalyst is used.

4. The process according to claim 3 , in which the molar ratio catalyst/solvent is comprised between 10 mol % and 50 mol %.

5. The process according to claim 1 in which chlorine is added during the reaction.

6. The process according to claim 1 , in which the product of the reaction is withdrawn in the gaseous state.

7. The process according to claim 1 , wherein a gas is injected.

8. The process according to claim 7 , in which the flow of gas, compared to the flow of the 1,1,2,3-tetrachloropropene is such that the molar ratio gas: 1,1,2,3-tetrachloropropene lies between 0.5:1 and 5:1.

9. The process according to claim 1 , wherein the reaction mixture obtained at (i) comprises, expressed as molar concentration, HCl between 20 and 60%,HF between 10 and 40%, 2-chloro-3,3,3-trifluoropropene between 5 and 20%, 1,1,1,2-tetrafluoro-2-chloropropane between 0.5 and 5%, 2,3-dichloro-3,3-difluuoropropene below 2% and solvent below 2%.

10. The process according to claim 1 , wherein separation (ii) is a distillation.

11. The process according to claim 1 , wherein the second stream is further separated into a HF stream containing mainly HF and an organic stream containing 2-chloro-3,3,3-trifluoropropene and 1,1,1,2-tetrafluoro-2-chloropropane.

12. The process according to claim 11 , wherein the organic stream is further purified.

13. The process according to claim 12 , wherein the organic stream is sent to a further conversion.

14. The process according to claim 1 , further comprising purging that withdraws heavies formed during (i).

15. The process for preparing 2,3,3,3-tetrafluoropropene, comprising:
(i) fluorination of 1,1,2,3-tetrachloropropene into 2-chloro-3,3,3-trifluoropropene according to claim 1 ;
(ii) converting 2-chloro-3,3,3-trifluoropropene into 2,3,3,3-tetrafluoropropene.

16. The process according to claim 15 , in which conversion in (ii) is a catalytic gas phase conversion.

Assignees

• Arkema France

Inventors

• Pigamo Anne

Classifications

• C07C21/18

  containing fluorine · CPC title

• C07C17/21

  with simultaneous increase of the number of halogen atoms · CPC title

• C07C17/206

  the other compound being HX · CPC title

• C07C17/383

  by distillation · CPC title

• C01B7/0712 Primary

  by distillation · CPC title