Quaternary arylcarboxylate compositions for extracting C1 to C4 carboxylic acids from aqueous streams

Patent metadata

Field	Value
Publication number	US-9611209-B1
Application number	US-201514973826-A
Country	US
Kind code	B1
Filing date	Dec 18, 2015
Priority date	Dec 18, 2015
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

This invention relates to solvents for extracting C 1 to C 4 carboxylic acids from aqueous streams. More specifically, the extraction solvents include one or more salts composed of a phosphonium cation and an arylcarboxylate anion. The extraction solvents may further include one or more non-ionic liquid organic solvents as an enhancer. The extraction solvents are useful for extracting aqueous mixtures containing one or more lower carboxylic acids, such as monocarboxylic acids, alkoxycarboxylic acids, and halogen-containing carboxylic acids.

First claim

We claim:

1. A composition for separating a C 1 to C 4 carboxylic acid from water, the composition comprising:
(a) a quaternary phosphonium arylcarboxylate salt;
(b) a hydrophobic non-ionic organic solvent;
(c) a C 1 to C 4 carboxylic acid; and
(d) water,
wherein the hydrophobic non-ionic organic solvent is not the extract, and
wherein the arylcarboxylate salt has the general formula 1:

wherein
R 1 , R 2 , R 3 and R 4 are each independently a C 1 to C 26 hydrocarbyl group, provided that R 1 , R 2 , R 3 , and R 4 collectively have a total of at least 24 carbon atoms; and
Ar is an aryl group having 6 to 24 carbon atoms.

2. The composition according to claim 1 , wherein Ar is substituted with a halogen, alkyl group, aryl group, halogen-substituted alkyl group, halogen-substituted aryl group, secondary alkyl or aryl amino group, tertiary alkyl or aryl amino group, halogen-substituted secondary alkyl or aryl amino group, halogen-substituted tertiary alkyl or aryl amino group, nitro group, alkyl or aryl ether group, halogen-substituted alkyl or aryl ether group, or combinations thereof.

3. The composition according to claim 1 , wherein the arylcarboxylate salt comprises a tetraalkylphosphonium salt of a benzoate anion selected from the group consisting of benzoate, 2-methyl benzoate, 3-methyl benzoate, 4-methylbenzoate, 4-methylamino benzoate, 4-trifluoromethoxy benzoate, 2-nitrobenzoate, pentafluorobenzoate, and 3-dimethylamino benzoate.

4. The composition according to claim 1 , wherein the arylcarboxylate salt comprises a trihexyl(tetradecyl)phosphonium salt of a benzoate anion selected from the group consisting of benzoate, 2-methyl benzoate, 3-methyl benzoate, 4-methylbenzoate, 4-methylamino benzoate, 4-trifluoromethoxy benzoate, 2-nitrobenzoate, pentafluorobenzoate, and 3-dimethylamino benzoate.

5. The composition according to claim 1 , wherein the arylcarboxylate salt comprises trihexyl(tetradecyl)phosphonium arylcarboxylate or trioctyl(methyl)phosphonium arylcarboxylate.

6. The composition according to claim 1 , which comprises at least two of the arylcarboxylate salts.

7. The composition according to claim 1 , wherein the hydrophobic non-ionic organic solvent is selected from the group consisting of higher carboxylic acids, ethers, esters, ketones, aromatic hydrocarbons, chlorinated hydrocarbons, and nitriles.

8. The composition according to claim 7 , wherein the higher carboxylic acid is selected from the group consisting of n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, n-hexanoic acid, 2-ethylbutyric acid, heptanoic acid, n-octanoic, 2-ethylhexanoic acids, nonanoic acids, decanoic acids, dodecanoic acids, stearic acid, oleic acid, linolenic acid, and mixed vegetable-derived acids.

9. The composition according to claim 7 , wherein the higher carboxylic acid is selected from the group consisting of benzoic acid, 4-methylaminobenzoic acid, trifluoromethoxybenzoic acid, and 3-dimethylaminobenzoic acid.

10. The composition according to claim 7 , wherein the hydrophobic non-ionic organic solvent is selected from the group consisting of ethyl acetate, n-propyl acetate, n-propyl formate, i-propyl acetate, i-propyl formate, n-butyl acetate, n-butyl formate, i-butyl acetate, i-butyl formate, n-propyl propionate, i-propyl propionate, 2-pentanone, 3-pentanone, methyl isobutyl ketone, 3-methyl-2-butanone, 2-hexanone, 2-heptanone, cyclohexanone, 4-methyl-2-pentanone, 2,4-dimethyl-3-pentanone, 5-methyl-2-hexanone, 4-heptanone, 2-octanone, 5-nonanone, 2,8-dimethyl-4-heptanone, 3,3,5-trimethyl cyclohexanone, isophorone, diethyl ether, methyl propyl ether, dipropyl ether, di-isopropyl ether, methyl t-butyl ether, tertiary amyl methyl ether, ethyl butyl ether, toluene, m-xylene, p-xylene, and o-xylene.

11. The composition according to claim 10 , wherein the hydrophobic non-ionic organic solvent is selected from the group consisting of methyl isobutyl ketone, toluene, isopropyl acetate, and methyl t-butyl ether.

12. The composition according to claim 1 , which comprises at least two of the hydrophobic non-ionic organic solvents.

13. The composition according to claim 1 , which comprises 10 to 90 weight percent of the arylcarboxylate salt and 10 to 90 weight percent of the hydrophobic non-ionic organic solvent.

14. The composition according to claim 1 , which comprises 50 to 90 weight percent of the arylcarboxylate salt and 10 to 50 weight percent of the hydrophobic non-ionic organic solvent.

15. A process for separating a C 1 to C 4 carboxylic acid from water, the process comprising:
contacting a feed mixture comprising a C 1 to C 4 carboxylic acid and water with an extraction solvent comprising a quaternary phosphonium arylcarboxylate salt and a non-ionic organic solvent at conditions effective to form (a) an extract mixture comprising the arylcarboxylate salt, the non-ionic organic solvent, and at least a portion of the C 1 to C 4 carboxylic acid from the feed mixture and (b) a raffinate mixture comprising water and less of the C 1 to C 4 carboxylic acid compared to the feed mixture,
wherein the non-ionic organic solvent is not the extract, and
wherein the arylcarboxylate salt has the general formula 1:

wherein
R 1 , R 2 , R 3 and R 4 are each independently a C 1 to C 26 hydrocarbyl group, provided that R 1 , R 2 , R 3 , and R 4 collectively have a total of at least 24 carbon atoms; and
Ar is an aryl group having 6 to 24 carbon atoms.

16. The process according to claim 15 , wherein the arylcarboxylate salt comprises a tetraalkylphosphonium salt of a benzoate anion selected from the group consisting of benzoate, 2-methyl benzoate, 3-methyl benzoate, 4-methylbenzoate, 4-methylamino benzoate, 4-trifluoromethoxy benzoate, 2-nitrobenzoate, pentafluorobenzoate, and 3-dimethylamino benzoate.

17. The process according to claim 15 , wherein the arylcarboxylate salt comprises trihexyl(tetradecyl)phosphonium arylcarboxylate or trioctyl(methyl)phosphonium arylcarboxylate.

18. The process according to claim 15 , wherein the extraction solvent comprises at least two of the arylcarboxylate salts.

19. The process according to claim 15 , wherein the non-ionic organic solvent is selected from the group consisting of higher carboxylic acids, ethers, esters, ketones, aromatic hydrocarbons, chlorinated hydrocarbons, and nitriles.

20. The process according to claim 19 , wherein the higher carboxylic acid is selected from the group consisting of n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, n-hexanoic acid, 2-ethylbutyric acid, heptanoic acid, n-octanoic, 2-ethylhexanoic acids, nonanoic acids, decanoic acids, dodecanoic acids, stearic acid, oleic acid, linolenic acid, and mixed vegetable-derived acids.

21. The process according to claim 19 , wherein the higher carboxylic acid is selected from the group consisting of benzoic acid, 4-methylaminobenzoic acid, trifluoromethoxybenzoic acid, and 3-dimethylaminobenzoic acid.

22. The process according to claim 19 , wherein the non-ionic organic solvent is selected from the group consisting of ethyl acetate, n-propyl acetate, n-propyl formate, i-propyl acetate, i-propyl formate, n-butyl acetate, n-butyl formate, i-butyl acetate, i-butyl formate, n-propyl propionate, i-propyl propionat

Assignees

• Eastman Chem Co

Inventors

• Liu Jingyi
• Wang Silu
• Hardacre Christopher
• Rooney David William
• Hembre Robert Thomas
• Barnicki Scott Donald
• Sink Chester Wayne

Classifications

• B01D11/0492

  Applications, solvents used · CPC title

• C07C51/48 Primary

  by liquid-liquid treatment · CPC title

• C07C51/44

  by distillation · CPC title

• Y02P20/54

  using solvents, e.g. supercritical solvents or ionic liquids · CPC title