| Electrochemical oxidation technology can destroy biologically toxic and refractory organic pollutant in wastewater effectively. Anode material is the key for organic pollutant degradation. Ti/SnO2-Sb electrode is one of the most promising anode materials used in electrochemical oxidation technology treating organic wastewater process. Rare earth elements co-doping Ti/SnO2-Sb electrode in order to improve electrode performances is a focus direction of present study. In the thesis, Ti/SnO2-Sb-Nd electrode co-doped with rare earth element Nd and its applications in organic wastewater treatment process were studied.Preparation conditions of Ti/SnO-Sb-Nd electrodes were optimized by orthogonal experiment design. The optimum preparation conditions were:Sb/Sn 12%, Nd/Sn 0.5%, thermal decomposition temperature 600℃, solvent n-butanol, solution concentration 1.0 mol·L-1, sintering schedule brushing-drying once followed by sintering. The results also illustrated that interaction exists between the preparation conditions.The influence mechanisms of Nd doping amounts and pyrolysis temperature on performances and characterization of Ti/SnO2-Sb-Nd electrode were studied. The influence of solvent and sintering schedule on performances and characterizations of Ti/SnO2-Sb-Nd electrode were revealed. The results showed that Nd doping induced transformation from Sb3+ to Sb5+, and improved lattice oxygen concentration in electrode coating. Electrodes with the best electro-catalytic oxidation activity and stability were prepared when Nd doping amount was 0.5%. Thermal decomposition temperature influenced crystallization of electrode coating and appropriate pyrolysis temperature ensured coating crystallize and growed fully. In the experiment,600℃was the appropriate pyrolysis temperature. Solvent and sintering schedule influenced electrode performances and characterizations observably when Ti/SnO2-Sb-Nd electrodes were prepared by brushing-thermal decomposition. In the experiment the best coating crystals were prepared when n-butanol was used as solvent, and at the same time n-butanol solvent protected titanium base from oxidation. Electrode with a cracked coating surface would be obtained probably if there are too much salt solute in electrode surface before sintering process, and usually the type of cracked coating surface is bad for electrode stability.Electrode failure process was analyzed through accelerate service life test. The results showed that there were chemical composition change stage and coating stripping stage in chronological order during the accelerated service life test. In chemical composition change stage, improvement of lattice oxygen concentration and transformation from Sb3+ to Sb5+ in electrode coating increased anode potential and cell voltage. After chemical composition change stage, coating stripping becomed the main change of electrode. When electrode coating was stripped so much that titanium base was exposed to electrolyte and TiO2 was generated, electrode accelerated service life terminated.Constant current treating simulated phenol wastewater (standing for organic wastewater) process by electrochemical system with Ti/SnO2-Sb-Nd anode was studied. The results showed that during constant current degradation process, anode potential was in oxygen evolution, and cell voltage variation was induced by anode potential variation; Phenol degradation was controlled by diffusion step; the early phenol degradation process followed first order kinetic equation; electric energy tended to be gotten fully used as organic pollutant concentration improved; electrode fouling phenomenon occured rarely on Ti/SnO2-Sb-Nd anode. The influence of aeration on degradation effect was studied and the results showed that aeration failed to improve degradation effects.
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