.ti / Sno <sub> 2 </ Sub> + Of Sb <sub> 2 </ Sub> The O <sub> 3 </ Sub> Electrode And Its Application In The Simulated Phenol Wastewater Treatment

Electrochemical degradation of phenol was investigated in this paper. The effects of preparation condition of Ti/SnO₂+Sb₂O₃ anodes, operation condition and anode materials on the electrochemical degradation process of phenol were studied.The effects of preparation condition, such as precursor solvents for SnO₂+Sb₂O₃, calcination temperature and Sb contents, on the microstructure, the morphology and lifetime were studied. The anode lifetime of the Ti/SnO₂+Sb₂O₃ anodes was assessed by the accelerated lifetime test and the microstructure and the morphology of the electrode were examined by means of XRD and SEM respectively. The experimental results show that the microstructure and morphology of the SnO₂+Sb₂O₃ layers are correlated to precursor solvents. Compared with Ethanol, Ethylene glycol and n-Butanol as precursor solvents for SnO₂+Sb₂O₃, the performance of Ti/SnO₂+Sb₂O₃ anodes obtained by polymeric precursor method (PPM) is higher. The Ti/SnO₂+Sb₂O₃ anodes prepared by PPM have a longer lifetime than those anodes prepared by other solvents. The electrochemical degradation of phenol synthetic wastewater using Ti/SnO₂+Sb₂O₃ electrodes prepared by PPM as anode performs good oxidation abilities and higher instantaneous current efficiency. When the temperature of calcinating is kept above 400℃, the polymeric precursor is decomposed and the anodes show better performance. The Ti/SnO₂+Sb₂O₃ anodes prepared by PPM at 500℃and 550℃perform identically oxidation abilities of phenol synthetic wastewater. Doping Sb can improve the performance of Ti/SnO₂+Sb₂O₃ anodes. The electrochemical activity of Ti/SnO₂+Sb₂O₃ anodes reduces for more Sb doped, about 5%-15% of Sb contents doped are comfortable, and the instantaneous current efficiency of electrochemical oxidation of phenol synthetic wastewater is higher. The effects of operating current density, reaction temperature and initial concentration of phenol on the efficiency of the electrochemical oxidation process of phenol synthetic wastewater were investigated using Ti/SnO₂+Sb₂O₃ anodes prepared by PPM at 500℃with 10% Sb contents. The chemical oxygen demand (COD) and instantaneous current efficiency (ICE) were determined during electrolysis. The experimental results show that the ICE rises up when increasing reaction temperature and initial concentration of phenol, decreases when increasing the operating current density.The Ti/SnO₂+Sb₂O₃, Ti/SnO₂+Sb₂O₃/PbO₂, Ti/SnO₂+Sb₂O₃/MnOx and Ti/SnO2 +Sb2O3/RuO2+PbO₂ electrodes were prepared and used as anodes for galvanostatic electrolysis in phenol synthetic wastewater, respectively. The effects of different anodes on the electrochemical oxidation of phenol synthetic wastewater were studied. The time dependences of COD and ICE were determined during electrolysis. The experimental results show that Ti/SnO₂+Sb₂O₃ electrodes perform good oxidation abilities and higher ICE, compared with Ti/SnO₂+Sb₂O₃/PbO₂, Ti/SnO₂+Sb₂O₃/MnO_x and Ti/SnO₂+Sb₂O₃/ RuO₂+PbO₂ electrodes used as anode. The voltammograms of the anodes in the phenol synthetic wastewater reveal that there is a higher oxygen evolution potential at Ti/SnO₂+Sb₂O₃ electrodes, which is interrelated with good oxidation abilities of Ti/SnO₂+Sb₂O₃ electrodes for phenol synthetic wastewater.