Evaluation of the simultaneous use of two compartments of an electrochemical reactor for the elimination of azo dyes

Abstract

In this work, an electrochemical reactor of parallel plates oxidized organic pollutants from the cathodic and anodic compartments. The Fenton reagent was produced in situ from the electrogenerated H2O2 in the cathode compartment to degrade 70 mg L−1 of acid orange 7 (AO7). The initial concentration was eliminated at the end of the treatment, where a removal of the chemical oxygen demand (COD) higher than 86% was observed. Simultaneously, the activation of H2O2 in the anodic compartment was studied, and it was evidenced that only 1.5 mM of H2O2 was able to activate during the 180 min treatment. However, there is some evidence that the activation continues after the process completion. A study of two concentrations of AO7 was conducted, 12 mg L−1 and 9 mg L−1 from which it was possible to eliminate 76% of the initial color for both cases. This work showed that it is possible to degrade polluting organic matter in the anodic section of a divided electrochemical reactor, although the concentrations that can be treated are very low. Finally, it was evident that the energy applied to the electrochemical reactor can be used to degrade textile effluents simultaneously in both chambers of the cell.