Catalyst and process using the catalyst for manufacturing fluorinated hydrocarbons

Patent metadata

Field	Value
Publication number	US-11452990-B2
Application number	US-201716331450-A
Country	US
Kind code	B2
Filing date	Sep 7, 2017
Priority date	Sep 7, 2016
Publication date	Sep 27, 2022
Grant date	Sep 27, 2022

Abstract

A catalyst comprising one or more metal oxides, wherein the catalyst has a total pore volume equal to or greater than 0.3 cm3/g and a mean pore diameter greater than or equal to 90 Å, where in the pore volume is measured using N2 adsorption porosimetry and the mean pore diameter is measured using N2 BET adsorption porosimetry.

First claim

The invention claimed is:

1. A fluorination catalyst comprising one or more metal oxides, wherein the catalyst does not comprise Ni, Pd, Al, or Pt, wherein the catalyst has a total pore volume equal to or greater than 0.4 cm 3 /g and a mean pore diameter greater than or equal to 90 Å, wherein the pore volume is measured using N 2 adsorption porosimetry and the mean pore diameter is measured using N 2 BET adsorption porosimetry, and wherein at least 80 wt % of the one or more metal oxides has an atomic ratio of oxygen to metal of 1.5.

2. The catalyst according to claim 1 , wherein the mean pore diameter of the catalyst is greater than or equal to 100 Å when measured by N 2 BET adsorption porosimetry.

3. The catalyst according to claim 1 , wherein the mean pore diameter of the catalyst is greater than or equal to 130 Å when measured by N 2 BJH adsorption porosimetry.

4. The catalyst according to claim 1 , wherein the mean pore diameter of the catalyst is greater than or equal to 90 Å when measured by N 2 BJH desorption porosimetry.

5. The catalyst according to claim 1 provided as a pellet or pellets comprising a plurality of catalyst particles.

6. The catalyst according to claim 5 , wherein the pellet or pellets comprise graphite.

7. The catalyst according to claim 5 , wherein the pellet or pellets have a longest dimension from about 1 mm to about 100 mm.

8. The catalyst according to claim 1 , wherein the catalyst comprises a transition metal.

9. The catalyst according to claim 8 , wherein the transition metal is chromium.

10. The catalyst according to claim 1 , wherein the catalyst is unused.

11. A process for manufacturing a tetrafluoropropene comprising contacting a hydro(halo)propene with HF in the presence of the catalyst according to claim 10 .

12. The process according to claim 11 , wherein the hydro(halo)propene comprises a hydrochlorofluoropropene.

13. A process for eliminating HF from a saturated C 2-3 hydrohalocarbon species, comprising contacting the species with the catalyst according to claim 10 .

14. A fluorinated catalyst according to claim 10 .

15. The catalyst according to claim 1 , wherein a metal in the catalyst is selected from the group consisting of Li, Na, K, Ca, Cs, Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Ru, Rh, Ir, Cu, Ag, Au, La, and Ce.

16. A method of preparing a catalyst as defined in claim 1 , comprising the steps of:
a) preparing a metal salt solution and a hydroxide solution;
b) combining the solutions at a pH of greater than 8.0 in order to precipitate a metal hydroxide(s);
c) drying the precipitated metal hydroxide(s); and
d) calcining the metal hydroxide(s) to form the metal oxide(s).

17. The method according to claim 16 , wherein step b) is carried out at a pH of greater than or equal to 8.5.

18. The method according to claim 16 , wherein the metal salt comprises a nitrate salt.

19. The method according to claim 16 , wherein the hydroxide solution comprises ammonium hydroxide (NH 4 OH).

20. The method according to claim 16 , wherein the metal salt solution is provided at a concentration of from about 1 mol/l to about 10 mol/l.

21. The method according to claim 16 wherein the hydroxide solution is provided at a concentration of from 1 mol/l to about 10 mol/l.

22. The method according to claim 16 , wherein step (b) is performed by combining the solutions in a body of solvent.

23. The method according to claim 16 , wherein step b) is carried out at a substantially constant temperature.

24. The method according to claim 16 , wherein step (b) is performed while agitating the combined solutions.

25. The method according to claim 16 , wherein the precipitate formed during step (b) comprises particles having average longest dimensions of from about 5 μm to about 20 μm.

26. The method according to claim 16 , wherein step (c) comprises removing liquid from the precipitated metal hydroxide(s) to produce a wet cake.

27. The method according to claim 26 , wherein the cake is washed prior to any drying or calcining.

28. The method according to claim 26 , wherein step (c) comprises removing liquid from the wet metal hydroxide(s) cake by exposing it to elevated temperature.

29. The method according to claim 28 , wherein the precipitate is exposed to the elevated temperature for at least 15 minutes.

30. The method according to claim 16 , wherein step (d) comprises a step of calcining the metal hydroxide(s), after liquid removal and/or drying.

31. The method according to claim 16 , wherein the calcining step comprises heating the metal hydroxide(s) to a temperature between about 200° C. and about 550° C.

32. The method according to claim 16 , wherein the calcining step is performed for a sufficient period to produce a catalyst having a TGA loss on ignition (LOI) of less than about 15%.

33. The method according to claim 16 further comprising combining the calcined metal oxide(s) with graphite to provide a catalyst composition comprising about 0.1 wt % to about 10 wt % graphite.

34. The method according to claim 16 , wherein the calcined metal oxide(s) and/or catalyst composition is pressed to form catalyst pellets.

35. The method according to claim 34 , wherein the pressing takes place under a load of about 1 to 100 tonnes.

36. The method according to claim 35 , wherein the pellets so formed have a longest dimension from about 1 mm to about 100 mm.

37. A process for fluorinating a C 2-3 hydrohalocarbon species, comprising contacting the species with the catalyst according to claim 1 .

38. The process according to claim 37 , comprising contacting trichloroethylene with the catalyst in the presence of HF to produce 1,1,1,2-tetrafluoroethane (134a).

39. The process according to claim 37 wherein the species is a C 3 hydrohalocarbon species.

40. The process according to claim 37 , wherein the method is conducted in the vapour phase.

41. A process for dehydrohalogenating a C 2-3 hydrohalocarbon species, comprising contacting the species with the catalyst according to claim 1 .

42. The process according to claim 41 , comprising contacting a hydro(halo)fluoropropane with the catalyst to produce a fluoropropene.

43. The process according to claim 42 , wherein the fluoropropene is a tetrafluoropropene (1234).

44. The process according to claim 43 , wherein the hydro(halo)fluoropropane comprises a compound selected from the group consisting of: 1,1,1,2,3-pentafluoropropane, 1,1,1,2,2-pentafluoropropane and/or 1,1,1,3,3-pentafluoropropane.

45. The process according to claim 43 , wherein the tetrafluoropropene comprises 1,3,3,3-tetrafluoropropene and/or 2,3,3,3-tetrafluoropropene.

46. A process for adding HF to an unsaturated C 2-3 hydrohalocarbon species, comprising contacting the species with the catalyst according to claim 1 .

Assignees

• Mexichem Fluor Sa De Cv

Inventors

• Rees Claire Nicola
• Mcguinness Claire Elizabeth
• Sharratt Andrew Paul

Classifications

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• B01J35/50

  characterised by their shape or configuration · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J23/26 Primary

  Chromium · CPC title

• C07C17/087

  to unsaturated halogenated hydrocarbons · CPC title