| Electrochemical catalytic oxidation technology has aroused extensive attention of researchers for its environmental compatibility and environmental friendly characteristics. Thus, the scholars focus their attention on developing the anode materials which have high catalytic activity and long service life. Preparation method and the structure of the matrix material are two influencing factors according to the electrode performance. Based on these two aspects, this paper is to design a reasonable reactor and produce a Ti/Sb-SnO2 porous tube electrode which has both electrocatalytic activity and membrane filtration.Using titanium filter tube instead of traditional titanium plate as the substrate, different preparation methods have been tried to produce a tubular porous Ti/Sb-SnO2 electrodes with different surface microstructure.The characterization results of SEM and pore size distribution test technology showed that electrode prepared by Pechini and ultrasonic immersion method, can significantly improve the aperture of porous electrode internal distribution by multiple processes. The average pore size decreased from 2.607 μm to 2.278 μm, which indicated the electrode has larger electrochemically active surface.LSV test shows that the oxygen evolution potential of tubular porous Ti/Sb-SnO2 electrode prepared by Pechini and ultrasonic immersion method in three kinds of medium acidic, neutral, alkaline were 2.02V,2.01V,1.10V. The pH value of the solution has great influence on oxygen evolution potential of the electrode. The oxygen evolution potential in alkaline conditions is lower than that in acidic condition. The oxygen evolution potential of the electrode prepared by Sol-gel method 1 is only 1.44V in 0.5 mol/L Na2SO4 solution.In order to explore whether the prepared electrode has the synergistic function of both electro catalytic oxidation and membrane filtration, pyridine wastewater is treated respectively in ordinary device and process combination device with the same electrode under other same electrolysis conditions. The results show that the removal rate of initial concentration 100mg/L pyridine wastewater is 51.96% and 69.89% respectively, further more the latter device has higher utilization rate of charge by calculating the instantaneous current efficiency.The treatment of pyridine simulative wastewater with the new tubular porous Ti/Sb-SnO2 electrode is studied. Factors affecting removal rate were investigated such as pyridine concentration, electrolyte concentration, current density and initial pH. The results show that the optimal parameter conditions of the pyridine concentration of 100mg/L are anhydrous sodium sulfate concentration of 10 g/L, current density of 30 mA/cm2, pH=3. After degradation time of 180min,the removal rate reached 100%.From the result obtained by UV, HPLC and IC analysis of water samples, the tubular porous Ti/Sb-SnO2 anode also has the ability to degrade the intermediate product. The degradation process of pyridine will produce the small molecular organic acid such as formic acid and acetic acid. Nitrate ion and nitrite ion was detected in the degradation process. It can be speculated C-N bond is broken in the surface of tubular porous Ti/Sb-SnO2 anode which makes pyridine ring opened and then be advantageous to subsequent degradation. |
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