Electrochemical mediated oxidation of phenol using Ti/IrO2 and Ti/Pt-SnO2-Sb2O5 electrodes

The indirect electrochemical oxidation of phenol was studied at Ti/IrO2 and Ti/Pt-SnO2-Sb2O5 electrodes by bulk electrolysis experiments under galvanostatic control. The obtained results clearly shown that the electrode material was an impor­tant para­me­ter for the optimization of such processes determining their mecha­nism and oxidation products. Different current efficiencies were obtained at Ti/IrO2 and Ti/Pt-SnO2-Sb2O5, depending on the applied current density in the range from 10, 20 and 30 mA cm−2. The effect of the amount of dissolved NaCl was studied also. It was observed that the electrochemical processes (direct/indirect) favor specific oxidation pathways depending on electrocatalytic material. Phenol degradation generates several intermediates eventually leading to complete mineralization, as indicated by the results obtained with the High-performance liquid chromatography (HPLC) technique