Effect of Dissolved Oxygen on the Efficiency of Electro-Fenton Process on Fe2O3/graphite Perforated Tubular Electrode

Abstract

Electrodes based on carbon materials modified with iron oxides or metallic iron have attracted much attention in the field of heterogeneous electro-Fenton process for the removal of various organic pollutants. In this study, perforated tubular graphite electrode modified with Fe2O3 (Fe2O3/GT) by electrochemical deposition was used as a cathode material. The obtained electrode was characterized by electron microscopy, energy-dispersive spectroscopy and Raman spectroscopy. The oxidation of rhodamine B in the electro-Fenton process by bubbling air through the perforated tubular graphite cathode at different air pressures was investigated. The complete decolorization of the rhodamine B solution was achieved in 20 min of electrolysis using Fe2O3/GT as a cathode at a current density of 29.85 mA/cm2 and a pressure of 0.1 MPa. The use of higher pressure leads to complications in the equipment design of the electro-Fenton process. Carrying out the electro-Fenton process at a pressure of 0.6 MPa leads to a decrease in the energy consumption by 0.07 kWh/mg. A possible mechanism for the oxidation of rhodamine B by bubbling air through the perforated tubular graphite cathode modified with Fe2O3 was proposed.