Kinetic study on the removal of organic pollutants by an electrochemical oxidation process

This paper deals with the kinetics of electrochemical oxidation of 2,6-dichlorophenol and p-hydroxybenzoic acid in phosphate buffer at pH = 7. On the basis of experimental results, a mathematical model was formulated which effectively describes the trend in time of the concentration of the organic compounds involved in the electrochemical oxidation process. The proposed kinetic model is based on a reaction mechanism which takes into account both the direct oxidation of the organic substrate at the electrode surface and the indirect oxidation, in the liquid phase, by means of electrogenerated oxidizing agents. The model well interprets the complex effect on the removal efficiency of such operating parameters as the current density, the linear velocity of the electrolyte, and the ratio between the anode surface and solution volume.