Process for the preparation of 2,3,3,3-tetrafluoropropene

Patent metadata

Field	Value
Publication number	US-10053404-B2
Application number	US-201615095911-A
Country	US
Kind code	B2
Filing date	Apr 11, 2016
Priority date	Dec 14, 2011
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

The present invention provides a process for preparing 2,3,3,3-tetrafluoropropene from 1,1,1,2,3-pentachloropropane and/or 1,1,2,2,3-pentachloropropane, comprising the following steps: (a) catalytic reaction of 1,1,1,2,3-pentachloropropane and/or 1,1,2,2,3-pentachloropropane with HF into a reaction mixture comprising HCl, 2-chloro-3,3,3-trifluoropropene, 2,3,3,3-tetrafluoropropene, unreacted HF, and optionally 1,1,1,2,2-pentafluoropropane; (b) separating the reaction mixture into a first stream comprising HCl and 2,3,3,3-tetrafluoropropene and a second stream comprising HF, 2-chloro-3,3,3-trifluoropropene and optionally 1,1,1,2,2-pentafluoropropane; (c) catalytic reaction of the second stream into a reaction mixture comprising 2,3,3,3-tetrafluoropropene, HCl, unreacted 2-chloro-3,3,3-trifluoropropene, unreacted HF and optionally 1,1,1,2,2-pentafluoropropane and (d) feeding the reaction mixture of step (c) directly without separation to step (a).

First claim

The invention claimed is:

1. A process for producing 2,3,3,3-tetrafluoropropene, comprising:
(a) reacting 1,1,1,2,3-pentachloropropane and/or 1,1,2,2,3-pentachloropropane with HF in the presence of a catalyst to produce a first reaction mixture comprising HCl, 2-chloro-3,3,3-trifluoropropene, 2,3,3,3-tetrafluoropropene, unreacted HF and optionally 1,1,1,2,2-pentafluoropropane, wherein the catalyst comprises a supported or unsupported catalyst containing at least one metal selected from the group consisting of Cr, Ni, Fe, Zn, Ti, V, Zr, Mo, Ge, Sn, Pb, Mg, Sb, Co, Ru, Rh, Pd, Os, Ir, Pt, Mn, Re, Sc, Y, La, Hf, Cu, Ag, Au, and metals having an atomic number of 58 through 71;
(b) separating the first reaction mixture into a first stream and a second stream comprising 2-chloro-3,3,3-trifluoropropene;
(c) reacting HF and the second stream in the presence of a catalyst to produce a second reaction mixture comprising 2,3,3,3-tetrafluoropropene, HCl, unreacted 2-chloro-3,3,3-trifluoropropene and HF and optionally 1,1,1,2,2-pentafluoropropane, wherein the catalyst comprises a supported or unsupported catalyst containing at least one metal selected from the group consisting of Cr, Ni, Fe, Zn, Ti, V, Zr, Mo, Ge, Sn, Pb, Mg, Sb, Co, Ru, Rh, Pd, Os, Ir, Pt, Mn, Re, Sc, Y, La, Hf, Cu, Ag, Au, and metals having an atomic number of 58 through 71; and
(d) feeding the second reaction mixture of step (c) directly to step (a).

2. The process of claim 1 , wherein the catalyst of step (a) is the same as the catalyst of step (c).

3. The process of claim 1 , wherein step (a) and step (c) are carried out in the gas phase.

4. The process of claim 1 , wherein the catalyst in step (a) and/or step (c) is a chromium based catalyst.

5. The process of claim 4 , wherein the catalyst is a mixed catalyst.

6. The process of claim 4 , wherein the catalyst is a supported catalyst.

7. The process of claim 1 , wherein step (a) and/or step (c) is carried out in the presence of oxygen or chlorine.

8. The process of claim 1 , wherein step (a) and/or step (c) is carried out at a temperature of 100 to 500° C.

9. The process of claim 1 , wherein step (a) and/or step (c) is carried out at a molar ratio of HF:organic feed from 4:1 to 100:1.

10. The process of claim 1 , wherein the molar ratio of oxygen:organic feed in step (a) and/ or step (c) is 0.005 to 2.

11. The process of claim 1 , further comprising separating HCl from the reaction mixture after step (a).

12. The process of claim 1 , wherein the reactor of step (c) is placed above the reactor of step (a).

13. The process of claim 1 , wherein the catalyst of any of step (a) or step (c) comprises one or more of chromium oxide, chromium oxyfluoride, chromium fluoride, aluminum fluoride, or aluminum oxyfluoride.

Assignees

• Arkema France

Inventors

• Deur-Bert Dominique
• Collier Bertrand
• Wendlinger Laurent

Classifications

• B01J37/24

  Chlorinating · CPC title

• B01J23/26

  Chromium · CPC title

• C01B7/191

  Hydrogen fluoride · CPC title

• C07C17/25 Primary

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

• C07C17/206

  the other compound being HX · CPC title