Method for the purification of acetic acid and acrylic acid

Patent metadata

Field	Value
Publication number	US-9944582-B2
Application number	US-201414787683-A
Country	US
Kind code	B2
Filing date	May 19, 2014
Priority date	May 20, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

The present disclosure relates to a method for purifying an acid, wherein the method comprises: a) producing a crude product mixture by a partial oxidation reaction, wherein the crude product mixture comprises acrylic acid and acetic acid; b) purifying the crude product mixture by distillation using a high-boiling solvent to purify the acrylic acid; and c) purifying the crude product mixture by distillation using a low-boiling solvent to purify the acetic acid.

First claim

What is claimed is:

1. A method for purifying an acid, wherein the method comprises:
a) producing a crude product mixture by a partial oxidation reaction, wherein the crude product mixture comprises acrylic acid and acetic acid;
b) contacting the crude product mixture with a high-boiling solvent to provide a high-boiling solvent containing acrylic acid, and a vapor stream containing acetic acid;
c) purifying the acrylic acid by distillation using the high-boiling solvent containing acrylic acid;
d) introducing the vapor stream containing acetic acid and a low-boiling solvent into a counter-current packed absorption column to absorb the acetic acid in the low-boiling solvent; and
e) purifying the acetic acid by separate distillation step using the low-boiling solvent absorbing acetic acid;
wherein the high-boiling solvent has a boiling point greater than 105° C.,
wherein the low-boiling solvent has a boiling point lower than acetic acid.

2. The method according to claim 1 , further comprising reacting the acrylic acid with the high-boiling solvent to produce an acrylate.

3. The method according to claim 1 , further comprising purifying the crude product mixture in the presence of an inhibitor to prevent acid polymerization.

4. The method according to claim 3 , wherein the inhibitor comprises a phenolic derivative.

5. The method according to claim 3 , wherein the inhibitor comprises hydroquinone, or an ether of hydroquinone, or a mixture thereof.

6. The method according to claim 3 , wherein the inhibitor comprises a phenothiazine derivative.

7. The method according to claim 3 , wherein the inhibitor comprises quinone, or benzoquinone, or a mixture thereof.

8. The method according to claim 3 , wherein the inhibitor comprises a metal thiocarbamate.

9. The method according to claim 3 , wherein the inhibitor comprises copper dibutyldithiocarbamate, or copper diethyldithiocarbamate, or copper salicylate, or a mixture thereof.

10. The method according to claim 3 , wherein the inhibitor comprises an amine.

11. The method according to claim 3 , wherein the inhibitor comprises a hydroxylamine, or a phenyldiamine, or a mixture thereof.

12. The method according to claim 1 , further comprising the addition of oxygen for inhibitor activation.

13. The method according to claim 1 , wherein the high-boiling solvent comprises an alcohol.

14. The method according to claim 1 , wherein the high-boiling solvent comprises a linear alcohol.

15. The method according to claim 1 , wherein the high-boiling solvent comprises hexanol, or heptanol, or octanol, or a mixture thereof.

16. The method according to claim 1 , wherein the high-boiling solvent comprises a branched alcohol.

17. The method according to claim 1 , wherein the high-boiling solvent comprises 2-ethyl hexanol.

18. The method according to claim 1 , wherein the high-boiling solvent comprises a polyhydric alcohol.

19. The method according to claim 1 , wherein the high-boiling solvent comprises ethylene glycol, or 1,3-propane diol, or 1,4-butane diol, or a mixture thereof.

20. The method according to claim 1 , wherein the high-boiling solvent comprises an amino alcohol.

21. The method according to claim 1 , wherein the high-boiling solvent comprises 2-dimethyl aminoethanol, or 2-diethyl aminoethanol, or a mixture thereof.

22. The method according to claim 1 , wherein the low-boiling solvent comprises isopropyl acetate, or water, or a mixture thereof.

23. The method according to claim 1 , wherein the partial oxidation reaction comprises propane as the starting material and a Mo-V-Ga-Pd-Nb-X mixed metal catalyst wherein X is La, Te, Ge, Zn, Si, In or W.

24. The method according to claim 1 , wherein the method further comprises the high-boiling solvent reacting downstream of the acrylic acid purification with the acrylic acid to form an acrylate.

25. The method according to claim 1 , wherein the crude product mixture further comprises water.

Assignees

• Saudi Basic Ind Corp

Inventors

• Karime Mustapha N
• Baksh Faisal
• Bashir Mubarik
• Nawaz Zeeshan

Classifications

• C07C67/08

  by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds · CPC title

• C07C51/44 Primary

  by distillation · CPC title

• C07C69/54

  Acrylic acid esters; Methacrylic acid esters · CPC title

• C07C51/215

  of saturated hydrocarbyl groups · CPC title

• C07C53/08

  Acetic acid (pyroligneous acid C10C; preparation of vinegar C12J) · CPC title