| Wastewater containing benzene series organic is harmful to environment and human with the feature of strong toxicity and refractory degradation. It is imperative to find effective method for the treatment of wastewater containing benzene series organic because of the difficulty of benzenoid wastewater treatment. Recently, the electrochemical oxidation process has attracted extensive attention and wide application because of the versatility and environmental compatibility in field of wastewater treatment. Electrode materials have great effect on the energy consumption and oxidative degradation efficiency in the process of degradation of organic pollutions. In this paper, the electrodes with excellent electrocatalytic activity and high stability were prepared and applied in the treatment of benzenoid wastewater. The main research contents of this research are as follows:The electrocatalytic degradation of m-dinitrobenzene in solution was investigated using stainless steel electrode as cathode and boron-doped diamond electrode as anode, which was prepared by microwave plasma chemical vapor deposition. It was shown that the removal efficiency of m-dinitrobezene was 82.7% within 150 min under the optimum reaction conditions of current density 10 m A cm-2, p H 7.0, 4.0 g L-1Na2SO4 electrolyte, 125 mg L-1m-dinitrobezene, and the degradation of m-dinitrobezene was fitted well with the first-order kinetics.Additionally, the UV and HPLC analyses demonstrated that m-dinitrobezene was totally destroyed and mineralized by electrocatalytic oxidation reaction within 240 min.Ti/Sn O2-Ru O2 electrode was prepared by brush coating method. The electrocatalytic degradation of 4-nitrobenzaldehyde in aqueous solution was investigated using as-prepared electrode as anode and stainless steel electrode as cathode. The optimum processing conditions in the degradation process were discussed, and it was found that the removal efficiencies of 4-nitrobenzaldehyde and CODCr were achieved at 79.8%and 82.3%, respectively, within 180 min in the presence of 8.0×10-2 mol L-1Na2SO4 electrolyte at applied voltage of 3 V and p H 2.5. Moreover,based on the analysis of removel efficiency of 4-nitrobenzaldehyde in whole degradation process, it was implied that the degradation of4-nitrobenzaldehyde was in accordance to first-order kinetics.Ti/Pb O2 electrode and novel Ti/Pb O2-Yb2O3 were prepared by electrodeposition technique. It was shown that Ti/Pb O2-Yb2O3 electrode possessed more compact structure, higher oxygen evolution potential and more excellent electrocatalytic performance. The effects on degradation of diazodinitrophenol were analyzed with Ti/Pb O2-Yb2O3 as anode and stainless steel electrode as cathode in a series of experiments. It was shown that the removal efficiencies of diazodinitrophenol and CODCr were about 92.9% and 89.5% within 150 min under the optimal reaction condition of current density 10 m A cm-2,p H 3.0, 12.5 g L-1Na2SO4 electrolyte, respectively.Ti/Sn O2-Sb-Cu electrode and Ti/Sn O2-Sb electrode were prepared by sol-gel process. The electrocatalytic degradation of 2,4,6-trinitrophenol in aqueous solution was investigated using as-prepared electrode as anode and stainless steel electrode as cathode. It was shown that the Ti/Sn O2-Sb-Cu electrode compared to Ti/Sn O2-Sb electrode had more compact structure and better electrical catalytic degradation performance. Under the optimum reaction condition of initial p H 3.0, 8.0 g L-1Na Cl electrolyte at current density of 5 m A cm-2,the removal efficiencies of 2,4,6-trinitrophenol and CODCr were about92.7% and 91.3%, respectively, after 150 min degradation.According to the experimental results, the electrochemical oxidation process is an efficient method, providing a broader strategy for treating of benzenoid wastewater. Additionally, the present work implies that Ti/Sn O2-Ru O2, boron-doped diamond, Ti/Pb O2-Yb2O3 and Ti/Sn O2-Sb-Cu electrodes have wide application prospect in removing of refractory pollutants. |
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