Process for the recovery of cobalt and tungstic acid and/or its derivatives from aqueous solutions

Patent metadata

Field	Value
Publication number	US-2023193420-A1
Application number	US-202318169259-A
Country	US
Kind code	A1
Filing date	Feb 15, 2023
Priority date	Jan 22, 2015
Publication date	Jun 22, 2023
Grant date	—

Abstract

This invention relates to a process for the recovery of cobalt ions and tungstic acid and/or its derivatives from aqueous solutions, such as in particular the spent catalytic waters deriving from processes for the oxidative cleavage of vegetable oils. In particular this invention relates to a process for the recovery of cobalt ions and tungstic acid and/or its derivatives which provides for the use of cation-exchange resins.

First claim

1 . A process for oxidative cleavage of vegetable oils containing monounsaturated fatty acid triglycerides comprising:
1) a first step of hydroxylation of the double bond present in the monounsaturated fatty acid triglycerides in the presence of a catalyst comprising tungstic acid and/or its derivatives, to yield a vicinal diol, 2) a subsequent second step of oxidation of the vicinal diol in the presence of catalysts comprising cobalt salts, thereby obtaining a mixture comprising saturated monocarboxylic acids and saturated carboxylic acid triglycerides having more than one acid group, 3) a step of separation of an aqueous solution containing cobalt ions and tungstic acid and/or their derivatives from the mixture of step 2) and 4) a step of separation of cobalt ions from said aqueous solution of step 3) comprising the operations of:
a) removing the cobalt ions by placing the aqueous solution in contact with a cation-exchange resin;
b) separating the aqueous solution from the cation-exchange resin;
c) concentrating the aqueous solution obtained from stage b, thereby obtaining a concentrated aqueous solution containing tungstic acid and/or its derivatives,
d) eluting cobalt ions from the cation-exchange resin in stage b, using an acid aqueous solution, thereby obtaining an aqueous solution comprising cobalt ions,

wherein the aqueous solution obtained at the end of step 4-d) is used to prepare the catalyst for the oxidation step 2).

2 . The process according to claim 1 wherein the tungstic acid derivatives of step 1) are selected from the group consisting of phosphotungstic acid, pertungstic acid and polytungstates and their cobalt salts.

3 . The process according to claim 1 wherein the cobalt salts of step 2) are selected from the group consisting of cobalt acetate, cobalt chloride, cobalt sulfate, cobalt nitrate and cobalt bromide.

4 . The process according to claim 1 , wherein at the end of step 4-c) the concentration of tungstic acid and/or its derivatives in the concentrated aqueous solution, expressed as tungsten concentration, is of between 10 and 15% by weight and the concentration of cobalt ions is of less than 50 ppm.

5 . The process according to claim 1 , comprising before step 4-a) a preliminary purification step for separating an organic phase from the aqueous solution.

6 . The process according to claim 5 , in which the separation of the organic phase is performed by decantation.

7 . The process according to claim 6 , in which the decantation is performed in presence of an organic solvent.

8 . The process according to claim 7 , in which the organic solvent is selected from the group consisting of n-hexane, n-heptane, n-octane, n-nonanoic acid and mixtures thereof.

9 . The process according to claim 8 , in which the organic solvent is n-octane, nonanoic acid or mixtures thereof.

10 . The process according to claim 1 , in which the cationic exchange resin is crosslinked.

11 . The process according to claim 1 , in which the cation-exchange resin is of the strong acid type.

12 . The process according to claim 11 , in which the functional group of the cation-exchange resin of the strong acid type is constituted by sulphonic groups.

13 . The process according to claim 1 , in which the step 4-a) is performed with an ionic exchange column.

14 . The process according to claim 13 , in which the aqueous solution is fed to step a) with a flow rate comprised between 1 and 50 BV*/h (LHSV).

15 . The process according to claim 2 , in which the step 4-a) is performed with an ionic exchange column.

16 . The process according to claim 3 , in which the step 4-a) is performed with an ionic exchange column.

17 . The process according to claim 4 , in which the step 4-a) is performed with an ionic exchange column.

18 . The process according to claim 5 , in which the step 4-a) is performed with an ionic exchange column.

19 . The process according to claim 6 , in which the step 4-a) is performed with an ionic exchange column.

20 . The process according to claim 7 , in which the step 4-a) is performed with an ionic exchange column.

Assignees

• Novamont Spa

Inventors

• Borsotti Giampietro
• Digioia Francesca

Classifications

• C02F1/26

  by extraction · CPC title

• B01J39/05

  in the strongly acidic form · CPC title

• C22B34/365

  from spent catalysts · CPC title

• B01J47/02

  Column or bed processes · CPC title

• B01J39/20

  obtained by reactions only involving unsaturated carbon-to-carbon bonds · CPC title