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

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).