Electrochemical Oxidation of Phenol on Ti-Based PbO2 Electrodes

Abstract:

Three kinds of Ti-based PbO2 electrodes with or without SnO2+Sb2O3 interlayers were prepared by the thermal decomposition of Pb(NO3)2 solution and applied as anodes to simulate the electrolytic degradation process of phenol in aqueous solution. The experimental results show that the cell voltages for the anodes with the interlayers are lower than that without the interlayers. There are little differences in the removal rate of phenol, the COD values and the instantaneous current efficiency for the three kinds of electrode. The phenol removal rate reaches 99.2% after degradation process for 3.0 h, and the COD value declines to15.7% after degradation process for 6.5 h for the Ti/SnO2+Sb2O3/PbO2 electrode obtained by a polymeric precursor method as an anode. The instantaneous current efficiencies of electrolysis process for the three kinds of electrodes decrease with increasing the electrolysis time. The electrocatalytic activity and the accelerated lifetime were assessed by cyclic voltammetry and accelerated life tests for the three kinds of anodes. It has been found that the accelerated lifetime and electrocatalytic activity of the electrodes with SnO2+Sb2O3 interlayer are improved obviously.

Key words:electrochemical oxidation; phenol; PbO2; Ti