Method for isolating a carboxylic acid from an aqueous solution

Patent metadata

Field	Value
Publication number	US-11299447-B2
Application number	US-201214366628-A
Country	US
Kind code	B2
Filing date	Dec 21, 2012
Priority date	Dec 23, 2011
Publication date	Apr 12, 2022
Grant date	Apr 12, 2022

Abstract

A method for manufacturing carboxylic acid that includes the following steps is provided. First, subjecting an aqueous mixture, including carboxylic acid and at least 5 wt. % dissolved magnesium chloride, to a forward extraction step using a first organic liquid, including an organic solvent, the organic solvent being selected from the group of C5+ ketones, thereby obtaining an organic carboxylic acid solution and an aqueous waste liquid including magnesium chloride. Second, subjecting the organic carboxylic acid solution to a back extraction step wherein the carboxylic acid is extracted from the organic carboxylic acid solution into an aqueous liquid, thereby obtaining an aqueous carboxylic acid solution and a second organic liquid. Third, subjecting the aqueous waste liquid including magnesium chloride derived from the forward extraction to a thermal decomposition step at a temperature of at least 300° C., thereby decomposing the magnesium chloride to magnesium oxide and HCl.

First claim

The invention claimed is:

1. Method for the recovery of carboxylic acid, the method comprising the steps of:
a) subjecting an aqueous mixture comprising carboxylic acid and at least 5 wt. % dissolved magnesium chloride, based on the total weight of water and dissolved material in the aqueous mixture to a forward extraction step, wherein the aqueous mixture subjected to the forward extraction step has a pH of 2 or lower, where the carboxylic acid is extracted from the aqueous mixture into a first organic liquid comprising at least 90% of an organic solvent, the organic solvent being selected from the group of C5-C8 ketones, to obtain an organic carboxylic acid solution and an aqueous waste liquid comprising magnesium chloride,
b) subjecting the organic carboxylic acid solution to a back extraction step where the carboxylic acid is extracted from the organic carboxylic acid solution into an aqueous liquid to obtain an aqueous carboxylic acid solution and a second organic liquid; and
c) subjecting the aqueous waste liquid comprising magnesium chloride obtained in the forward extraction to a thermal decomposition step at a temperature of at least 300° C. to decompose the magnesium chloride to magnesium oxide and HCl; wherein
the carboxylic acid is at least one member selected from the group consisting of: glycolic acid; butyric acid; valeric acid; succinic acid; propionic acid; 3-hydroxypropionic acid; 2-hydroxybutyric acid; 3-hydroxybutyric acid; 4-hydroxybutyric acid; citric acid;
fumaric acid; itaconic acid; adipic acid; acrylic acid; levulinic acid; maleic acid; 2,5-furandicarboxylic acid; mandelic acid; malic acid; and tartaric acid.

2. Method according to claim 1 , wherein the aqueous mixture comprising carboxylic acid and the at least 5 wt. % dissolved magnesium chloride of step a) is obtained by:
subjecting a carbon source to a fermentation step to form a carboxylic acid, which fermentation step comprises the steps of fermenting a carbon source by means of a micro-organism in a fermentation broth to form carboxylic acid and neutralizing at least part of the carboxylic acid by adding a magnesium base selected from magnesium oxide and magnesium hydroxide to obtain a magnesium carboxylate; and
subjecting the magnesium carboxylate to an acidification step where the magnesium carboxylate is contacted with HCl in an aqueous environment to form an aqueous mixture comprising carboxylic acid and magnesium chloride.

3. Method according to claim 1 , wherein the aqueous mixture subjected to the forward extraction step comprises at least 15 wt. % dissolved magnesium chloride, based on the total weight of water and dissolved material in the aqueous mixture.

4. Method according to claim 1 , wherein said first organic liquid comprises at least 95 wt. % of said organic solvent.

5. Method according to claim 1 , wherein the carboxylic acid is selected from the group consisting of: propionic acid; acrylic acid; butyric acid; and valeric acid.

6. Method according to claim 1 , wherein said first organic liquid used in the extraction step a) comprises substantially no extractants, said extractants being compounds which form a complex with the carboxylic acid to be extracted.

7. Method according to claim 1 , wherein the organic liquid is essentially free of amines, ethers, and alcohols, which means that these compounds, if present at all, are each present in an amount of less than 2 wt. % calculated on the weight of the organic liquid.

8. Method according to claim 1 , wherein the aqueous mixture subjected to the forward extraction step has a pH of 0-1.

9. Method according to claim 1 , wherein the aqueous mixture comprising carboxylic acid and magnesium chloride obtained from the acidification step is subjected to a concentration step comprising concentrating the aqueous mixture prior to extraction to a dissolved salt concentration of at least 5 wt. %, based on the total weight of water and dissolved material in the aqueous mixture.

10. Method according to claim 2 , wherein at least part of the HCl from the thermal decomposition step c) is recycled to the acidification step after having been dissolved in water to obtain a HCl-containing solution.

11. Method according to claim 2 , wherein the magnesium oxide formed in the thermal decomposition step c) is converted to magnesium hydroxide, which is added as magnesium base to the fermentation step.

12. Method according to claim 2 , wherein at least part of the magnesium oxide formed in the thermal decomposition step c) is recycled to the fermentation step, in the form of MgO or after conversion into magnesium hydroxide.

13. Method according to claim 2 , wherein at least part of the HCl from the thermal decomposition step c) is recycled to the acidification step.

14. Method according to claim 1 , wherein the carboxylic acid is at least one member selected from the group consisting of: succinic acid;
propionic acid; 3-hydroxypropionic acid; citric acid; fumaric acid; itaconic acid; adipic acid;
acrylic acid; levulinic acid; maleic acid; 2,5-furandicarboxylic acid; mandelic acid; malic acid; tartaric acid; 2-hydroxybutyric acid; 3-hydroxybutyric acid; and 4-hydroxybutyric acid.

15. Method according to claim 1 , wherein the carboxylic acid is at least one member selected from the group consisting of: succinic acid;
propionic acid; 3-hydroxypropionic acid; citric acid; 2-hydroxybutyric acid; 3-hydroxybutyric acid; and 4-hydroxybutyric acid.

16. Method according to claim 1 , wherein said first organic liquid used in the extraction step a) comprises substantially no amine extractants, said amine extractants being amine compounds which form a complex with the carboxylic acid to be extracted.

17. Method according to claim 1 , wherein said first organic liquid comprises at least 99 wt. % of said organic solvent.

18. Method according to claim 1 , wherein the aqueous mixture subjected to the forward extraction step comprises at least 20 wt. % dissolved magnesium chloride, based on the total weight of water and dissolved material in the aqueous mixture.

19. Method according to claim 1 , wherein the aqueous mixture subjected to the forward extraction step comprises at least 25 wt. % dissolved magnesium chloride, based on the total weight of water and dissolved material in the aqueous mixture.

20. Method according to claim 13 , wherein said HCl is recycled to the acidification step in gaseous form.

21. Method according to claim 2 , wherein said acidification step is conducted on a mixture of carboxylic acid and magnesium carboxylate.

22. Method for the recovery of carboxylic acid, said method comprising the steps of:
a) subjecting an aqueous mixture comprising carboxylic acid and at least 5 wt. % dissolved magnesium chloride, based on the total weight of water and dissolved material in the aqueous mixture to a forward extraction step where the carboxylic acid is extracted from the aqueous mixture into a first organic liquid comprising at least 90 wt. % of an organic solvent, the organic solvent being selected from the group of C5-8 ketones, thereby obtaining an organic carboxylic acid solution and an aqueous waste liquid comprising magnesium chloride;
b) subjecting the organic carboxylic acid solution to a back extraction step where the carboxylic acid is extracted from the organic carboxylic acid solution into an aqueous liquid to obtain a second organic liquid and an aqueous carboxylic acid solution whose concentration of carboxylic acids is higher than that of th

Assignees

• Purac Biochem Bv

Inventors

• De Haan André Banier
• Van Krieken Jan
• Ðekic {Hacek Over (Z)}Ivkovic Tanja

Classifications

• B01D11/0426

  Counter-current multistage extraction towers in a vertical or sloping position · CPC title

• C07C57/15

  Fumaric acid · CPC title

• C12P7/56 Primary

  Lactic acid · CPC title

• C12P7/44 Primary

  Polycarboxylic acids · CPC title

• B01D11/04

  of solutions which are liquid · CPC title