Process for producing 2, 3, 3, 3-tetrafluoropropene and 1, 1-difluoroethylene

Patent metadata

Field	Value
Publication number	US-9315432-B2
Application number	US-201414486143-A
Country	US
Kind code	B2
Filing date	Sep 15, 2014
Priority date	Mar 14, 2012
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

To provide an economically advantageous process for producing HFO-1234yf useful as a new refrigerant in sufficiently high yield by one reaction involving thermal decomposition. A process for producing HFO-1234yf and VdF from raw material containing R22, R40 and TFE, by a synthetic reaction involving thermal decomposition, which comprises (a) a step of supplying the R22, the R40 and the TFE to a reactor, as preliminarily mixed or separately, (b) a step of supplying a heat medium to the reactor, and (c) a step of bringing the heat medium in contact with the R22, the R40 and the TFE in the reactor to form the HFO-1234yf and the VdF.

First claim

What is claimed is:

1. A process for producing 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene from chlorodifluoromethane, chloromethane and tetrafluoroethylene, the process comprising:
(a) supplying chlorodifluoromethane, chloromethane and tetrafluoroethylene to a reactor, as preliminarily mixed or separately,
(b) supplying a heat medium to the reactor, and
(c) contacting the heat medium with chlorodifluoromethane, chloromethane and tetrafluoroethylene in the reactor to form a reaction product comprising 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene.

2. The process according to claim 1 , wherein a molar ratio of tetrafluoroethylene to chlorodifluoromethane supplied to the reactor ranges from 0.01 to 100.

3. The process according to claim 1 , wherein a molar ratio of chloromethane to chlorodifluoromethane and tetrafluoroethylene in total supplied to the reactor ranges from 0.1 to 10.

4. The process according to claim 1 , wherein chloromethane is supplied to the reactor at a temperature of from 0 to 1,200° C.

5. The process according to claim 1 , wherein chlorodifluoromethane is supplied to the reactor at a temperature of from 0 to 600° C.

6. The process according to claim 1 , wherein tetrafluoroethylene is supplied to the reactor at a temperature of from 0 to 1,200° C.

7. The process according to claim 1 , wherein a temperature in the reactor in said contacting (c) is adjusted to be from 400 to 1,200° C.

8. The process according to claim 1 , wherein the heat medium is supplied to the reactor at a temperature of from 100 to 1,200° C.

9. The process according to claim 1 , wherein the heat medium is at least one selected from the group consisting of steam, nitrogen and carbon dioxide.

10. The process according to claim 1 , wherein the heat medium is supplied at an amount of from 20 to 98 vol % in an entire gas supplied to the reactor.

11. The process according to claim 1 , wherein gas supplied to the reactor has a contact time in the reactor of from 0.01 to 10 seconds.

12. The process according to claim 1 , wherein a pressure in the reactor is from 0 to 2 MPa by gauge pressure.

13. The process according to claim 1 , wherein at least one selected from the group consisting of chlorotrifluoroethylene, trifluoroethylene, hexafluoropropene and octafluorocyclobutane, is further supplied to the reactor.

14. The process according to claim 1 , wherein
the reaction product further comprises chlorotrifluoroethylene, and
a molar ratio of 2,3,3,3-tetrafluoropropene to chlorotrifluoroethylene in the reaction product is ≧9.0.

15. The process according to claim 1 , further comprising:
(d) after said contacting (c), withdrawing from the reactor a reaction mixture comprising 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene formed in the reactor,
wherein said supplying (a), said supplying (b), and said withdrawing (d) are continuously carried out.

Assignees

• Asahi Glass Co Ltd

Inventors

• Furuta Shoji
• Takeuchi Yu

Classifications

• C07C17/25

  by splitting-off hydrogen halides from halogenated hydrocarbons · CPC title

• C07C17/269 Primary

  of only halogenated hydrocarbons · CPC title

• C07C21/18

  containing fluorine · CPC title