Stabilization of an aqueous solution of an organic iron salt

Patent metadata

Field	Value
Publication number	US-9988574-B2
Application number	US-201314387501-A
Country	US
Kind code	B2
Filing date	Mar 27, 2013
Priority date	Mar 30, 2012
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

Process and station for stabilizing an aqueous solution of an iron salt of an organic acid with a ferric component and a ferrous component of less solubility than the ferric component, such as the aqueous solution based on the Fe 3+ salt of meso-tartaric acid. To stabilize the content of the dissolved ferric salt, the solution is at least partly subjected to electrolytic oxidation.

First claim

The invention claimed is:

1. A process for stabilizing an aqueous solution comprising an iron complex of an organic acid with a ferric component and a ferrous component of less solubility than the ferric component, the process comprising at least partly subjecting the aqueous solution to electrolytic oxidation, wherein the aqueous solution has a pH between 3 and 5.

2. The process according to claim 1 , wherein the aqueous solution comprises an Fe3+ complex of meso-tartaric acid.

3. The process according to claim 2 , wherein the electrolytic oxidation is carried out in at least one electrolytic cell, with a separated anode and cathode.

4. The process according to claim 3 , wherein the aqueous solution comprises FeMTA and is circulated along the anode of one or more of the at least one electrolytic cells.

5. The process according to claim 3 , wherein the anode and cathode are separated by a porous or a non-porous separator.

6. The process according to claim 5 , wherein the anode and cathode are separated by a non-porous separator comprising at least one of an anion exchange membrane or a cationic exchange membrane.

7. The process according to claim 6 , wherein the aqueous solution comprises FeMTA and is circulated along the anode of one or more of the at least one electrolytic cells.

8. The process according to claim 6 , wherein the aqueous solution comprises FeMTA and has an iron content below 5 wt. % by weight of the total solution, and wherein the electrolytic oxidation is carried out to maintain the Fe2+ content below 3 wt. % by weight of the total iron content.

9. The process according to claim 6 , wherein the electrolytic cell comprises a catholyte of 1-3 M HCl aqueous solution.

10. The process according to claim 9 , wherein the aqueous solution comprises FeMTA and is circulated along the anode of one or more of the at least one electrolytic cells.

11. The process according to claim 1 , wherein the aqueous solution comprises FeMTA and has an iron content below 5 wt. % by weight of the total solution, and wherein the electrolytic oxidation is carried out to maintain the Fe2+ content below 3 wt. % by weight of the total iron content.

12. The process according to claim 1 , wherein at least 50 wt. % of the Fe2+ in the aqueous solution is oxidized to Fe3+.

13. The process according to claim 1 , wherein at least 90 wt. % of the Fe2+ in the aqueous solution is oxidized to Fe3+.

14. A station for preparing an aqueous solution, wherein the station comprises at least one electrolytic cell comprising the aqueous solution for the oxidation of Fe2+, and wherein the solution comprises an iron complex of an organic acid with a ferric component and a ferrous component of less solubility than the ferric component, and the aqueous solution has pH between 3 and 5.

15. The station according to claim 14 , wherein the at least one electrolytic cell comprises an anode, a cathode, and a separator separating the anode from the cathode.

16. The station according to claim 15 , wherein the separator is a non-porous anionic or cationic exchange membrane.

17. The station according to claim 16 , wherein the anode comprises a porous structure forming part of a circulation loop, and wherein the anode is at least partly positioned against the separator.

18. The station according to claim 16 , wherein an anolyte space between the anode and the separator is part of a circulation loop.

19. The station according to claim 18 , wherein the anode comprises a porous structure forming part of a circulation loop, and wherein the anode is at least partly positioned against the separator.

20. A dispensing station for dosing an aqueous solution of an iron complex of an organic acid with a ferric component on salt, wherein the dispensing station for dosing comprises at least one electrolytic cell comprising a aqueous solution for the oxidation of Fe2+, and wherein the solution comprises an iron complex of an organic acid with a ferric component and a ferrous component of less solubility than the ferric component, and the aqueous solution has a pH between 3 and 5.

Assignees

• Akzo Nobel Chemicals Int Bv

Inventors

• Lammers Hans
• Meijer Johannes Albertus Maria

Classifications

• C09K15/06 Primary

  containing oxygen · CPC title

• C25B1/00 Primary

  Electrolytic production of inorganic compounds or non-metals · CPC title

• C01D3/26 Primary

  Preventing the absorption of moisture or caking of the crystals · CPC title

• Y02P10/20

  Recycling · CPC title

• C25B9/08

  Chemistry & Metallurgy · mapped topic