Removal of organic pollutants from industrial wastewater by electrogenerated Fenton’s reagent

This study was performed to investigate the treatment of an industrial wastewater mainly containing naphthalene- and anthraquinone-sulphonic acids, by electrogenerated Fenton’s reagent. The hydrogen peroxide was produced in situ by electrochemical reduction of oxygen on graphite-felt cathodes and the Fe2+ ions were also regenerated by cathodic reduction of Fe3+. The influence of cathode potential, Fe2+ concentration and electrode surface pre-treatment on chemical oxygen demand (COD) removal and colour fading were studied. Results indicated that the higher COD removal was obtained in the presence of 3mM of ferrous ions working at a constant potential of _1V vs. SCE. Moreover, it was shown that both chemical and electrochemical pre-treatments of the cathode surface resulted in a decrease of COD depletio