Process for Purifying (Hydro)Fluoroalkenes

Patent metadata

Field	Value
Publication number	US-2016115105-A1
Application number	US-201614986802-A
Country	US
Kind code	A1
Filing date	Jan 4, 2016
Priority date	Oct 15, 2009
Publication date	Apr 28, 2016
Grant date	—

Abstract

The invention relates to a process for removing one or more undesired (hydro)halocarbon compounds from a (hydro)fluoroalkene, the process comprising contacting a composition comprising the (hydro)fluoroalkene and one or more undesired (hydro)halocarbon compounds with an aluminium-containing absorbent, activated carbon, or a mixture thereof.

First claim

1 . A process for removing one or more undesired (hydro)halocarbon compounds containing a ═CHF or a ═CF 2 moiety from a desired (hydro)fluoroalkene which does not contain a ═CF 2 moiety, the process comprising contacting, a composition comprising the desired (hydro)fluoroalkene and one or more undesired (hydro)halocarbon compounds with an aluminium-containing adsorbent, activated carbon, or a mixture thereof.

2 . The process according to claim 1 , wherein the desired (hydro)fluoroalkene is a hydrofluoroalkene.

3 . The process according to claim 1 wherein the desired (hydro)fluoroalkene is a C 3-7 (hydro)fluorealkene.

4 . The process according to claim 3 wherein the C 3-7 hydro)fluoroalkene is a hydrofluoropropene.

5 . The process according to claim 4 wherein the hydrofluoropropene is a trifluoropropene or a tetrafluoropropene.

6 . The process according to claim 5 wherein die trifluoropropene is 3,3,3-ttifluoropropene (R-1243zf).

7 . The process according to claim 5 wherein the tetrafluoropropene is E/Z-1,3,3,3-tetrafluoropropene (R-1234zc).

8 . The process according to claim 5 wherein the tetrafluoropropene is 2,3,3,3-tetrafluoropropene (R-1234yf).

9 . The process according to claim 1 wherein the or each undesired (hydro)halocarbon is selected from (hydro)fluoroalkenes and (hydro)chlorofluoroalkenes.

10 . The process according to claim 9 wherein the undesired (hydro)halocarbon is 1,1,3,3,3-pentafluoropropene (R-1225zc) or 1,2,3,3,3-pentafluoropropene (R-1225ye).

11 . The process according to claim 1 wherein the aluminium-containing adsorbent is a molecular sieve (zeolite) having pore sizes in the range 3 to 12 Angstroms.

12 . The process according to claim 1 wherein the activated carbon is impregnated with an additive selected from a metal, a metal compound, a base and a mixture thereof.

13 . The process according to claim 12 wherein the additive is an alkali metal salt.

14 . The process according to claim 1 wherein the activated carbon has a surface area of from 50 to 3000 m2.

15 . The process according to claim 14 wherein the activated carbon has a surface area of from 100 to 2000 m2.

16 . The process according to claim 15 wherein the activated carbon has a surface area of from 200 to 1500 m2.

17 . The process according to claim 1 wherein the or each undesired (hydro)halocarbon compound is present in an amount of from about 0.1 to about 1000 ppm, based on the weight of the composition comprising the desired (hydro)fluoroalkene and one or more undesired (hydro)halocarbon compounds.

18 . The process according to claim 17 wherein the or each undesired (hydro)halocarbon compound is present in an amount of from 0.1 to 500 ppm.

19 . The process according to claim 18 wherein the or each undesired (hydro)halocarbon compound is present in an amount of from 1 to 100 ppm.

20 . The process according to claim 1 wherein at least 50% of the undesired compound(s) present in the composition is removed therefrom.

21 . The process according to claim 20 wherein at least 70% of the undesired compound(s) in the composition is removed therefrom.

22 . The process according to claim 21 wherein at least 90% of the undesired compound(s) in the composition is removed therefrom.

23 . The process according to claim 1 wherein the process is conducted at a temperature of from 50° C. to 200° C.

24 . The process according to claim 23 wherein the process is conducted at a temperature of from 0° C. to 100° C.

25 . The process according to claim 24 wherein the e process is conducted at a temperature of from 10° C. to 50 C.

26 . The process according to claim 1 wherein following the contacting step, the resulting composition comprises the desired (hydro)fluoroalkene and from about 0 to about 10 ppm of the or each undesired (hydro)halocarbon compounds.

27 . The process according to 26 wherein following the contacting step, the resulting composition comprises the desired (hydro)fluoroalkene and from about 0 to about 5 ppm of the or each undesired (hydro)halocarbon compounds.

28 . The process according to claim 1 wherein the composition comprising the desired (hydro)fluoroalkene and one or more undesired (hydro)halocarbon compounds is a product stream from a process for producing the desired (hydro)fluoroalkene.

29 . The process for removing one or more undesired (hydro)halocarbon compounds from a desired (hydro)fluoroalkene according to claim 28 , which process is combined with one or more distillation, condensation or phase separation steps, and/or by scrubbing with water or aqueous base.

30 . The process according to claim 1 wherein the composition comprising the desired (hydro)fluoroalkene and one or more undesired (hydro)halocarbon compounds is contacted with an aluminium-containing adsorbent.

Assignees

• Mexichem Amanco Holding Sa

Inventors

• Sharratt Andrew P
• Mcguiness Claire E
• Hayes John

Classifications

• C07C17/206

  the other compound being HX · CPC title

• C07C17/389 Primary

  by adsorption on solids · CPC title

• C07C17/383

  by distillation · CPC title

• C07C17/25

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

• C07B63/00

  Purification; Separation (separation of optically-active compounds C07B57/00); Stabilisation; Use of additives · CPC title