Study On Simultaneous Effects Of PEG Doped Lead Dioxide Anode And Electro-fenton Reaction Electrocatalytic Oxidation Of Organic Pollutants

Dimensionally Stable Anode(DSA) and gas diffusion electrode made of mesoporous carbons/PTFE were prepared. The feasibility of synergetic effects of anode-cathode for the electrochemical degradation of the biorefractory organics were studied.The results of the tests were as follow:A polyethylene glycol(PEG) doped Ti/Sb-SnO2/PEG-PbO2 electrodes were prepared and characterized by linear sweep voltammetry(LSV), scanning electron microscopy(SEM), x-ray diffraction(XRD), chronoamporometric experiments, accelerated lifetime test. It was shown that PEG doped PbO2 electrode exhibited high electrocatalytic activity and good stability with the optimal PEG doped concentration of 9 g/L. The oxygen evolution potential of the prepared electrode reached 2.48 V, and its lifetime was 114 h, which was 3.35 times longer than that of the unmodified one. The electrochemical degradation performance of the prepared electrodes were investigated using o-cresol as a model. The percentage of o-cresol removal was decreased with the increase of the initial o-cresol concentration. The removal efficiency of o-cresol reached 100% in the condition of initial o-cresol concentration 100 mg/L, pH 10.0, and current density 10 mA/cm2 for 1.5h. The cyclic voltammetric(CV) test showed that the degradation of o-cresol on Ti/Sb-SnO2/PEG-PbO2 was achieved via electrochemical oxidation mediated by ·OH, and kinetic analyses indicated that the degradation of o-cresol followed first-order reaction.By using an gas diffusion electrode(GDE) fabricated from a carbon material with highly-ordered pores and large surface area(CMK-3) which can be used as cathode in the electro-Fenton system. The gas diffusion electrode can convert O2 to H2O2 effectively. The factors affecting the removal rate, such as inital current density, pH Value and initial concentration were also discussed. Under the conditions of a supporting electrolyte concentration of 0.1 mol/L, a pH of 3, inital current density of 9 mA/cm2, aeration rate of 1.5L/min, after 150 min electrolysis,122mg/L H2O2 was generated on the electrode.In this issue, Ti/Sb-SnO2/PEG-PbO2 and CMK-3/PTFE were employed as anode and cathode, respectively, a novel electro-Fenton and anodic oxidation system was designed for wastewater treatment. Key factors affecting the performance of electrodes were also investigated. The results showed that current density, pH value, initial contents had important influence on the electrode performance. The degradation ratio on this novel electrochemical oxidation system attained 100% after 120 min of electrolysis at a current density of 9 mA/cm2 with a 0.1mol/L Na2SO4 supporting electrolyte solution.