Method of purification of a redox mediator before electrolytic regeneration thereof

A method for purifying a Redox mediator used in a chemical process of oxidation of organic compounds before said mediator is regenerated in an electrolysis cell, comprising:

• recovering the mediator in the form of a solution containing volatile, soluble and insoluble impurities;
• subjecting the solution containing the mediator to a thermal treatment, said treatment being carried out in a reactor that is maintained at a temperature that is high enough to allow oxidation of the impurities by means of the left-over unused catalyst present in the solution and to simultaneously allow elimination of the volatile impurities present in the solution;
• and
• filtering the solution that contains the mediator to remove the insoluble impurities therefrom.