| For nearly 30 years, the electrochemical oxidation technology has developed rapidly. The experts and scholars in the field of environmental protection begin to pay wide attention to this new technology. The core technology of electrochemical oxidation is developing high performance anode materials. The anode materials must satisfy the conditions of high electricity catalytic activity, long life and so on. However, at present, the anode materials can not satisfy these conditions at the same time, which limit the electrochemical technology widely to be used in wastewater treatment engineering.This paper aims to preparate Ti/PbO2 electrode, a kind of anode materials with high electricity catalytic performance and long service life. Following are the main research: The new preparation technology of Ti/PbO2 electrode is explored and characterized; The Ti/PbO2 electrode was used to treatment phenol simulation wastewater; The Ti/PbO2 electrode modifed by doping Sn is developed and characterized.The technology of PbO2 anode oxidation has been already successfully transplanted to titanium foundation through the cathode deposition and the anodic oxidation process. The result proves that, the surface of Ti/PbO2 electrode is compact, and the surface oxide coating and interface layer are combining closely so that it is not easy to fall off. The electrochemical catalytic activity is high, and oxygen evolution potential is up to 1.60 V in neutral solution (0.1 mol/L Na2SO4). The performance of the electrode is stable, and the aging test results that its servive life time can reach to 333 days under industrial conditions (current density of 100 mA cm-2). When electrochemical oxidation technology used in water treatment engineering controling the current density between 10-40 mA cm-2, service life time of electrode can reach to 5.7 years.The treatment of phenol in simulative wastewater with the new PbO2 anode is studied. Factors affecting removal rate were investigated, such as voltaic density, initial pH, electrolyte concentration and phenol concentration. At the optimal conditions, when the amount of charge through reaches to 6 Ah L-1, the phenol concentration of 200mg/L and 1000 mg L of wastewater phenol removal rates reach to 90.1%,71.0%. and the COD removal efficiency reach to 34.2%,20.0%, respectively. The absolute removal of phenol are 181mg/L,710mg/L, the absolut removale of COD were 164mg/L,480mg/L, respectively.The modification of PbO2 electrode has realized through oxidating terne metal anode that mixed with different levels of Sn. By XRD and SEM analysis, it is found that with doping Sn, theβ-PbO2/α-PbO2 ratio and the PbO2 layer structure of Pb-Sn alloy are changed. Sn on the surface of terne metal is oxidated, and the Sn4+ induced to PbO2 layer, which can reduce the activation energy and the oxygen evolution over potential in the reaction process.The surface of Ti/Sn-PbO2 electrode is compact, which is made by oxidation of terne metal containing 3.5% Sn, and has large specific surface areas and strongest electricity catalytic activity. The potential oxygen evolution of the Ti/Sn-PbO2 electrode can reach to 1.75 V. |
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