为探寻硝基芳香族有机污染物的高效降解技术,采用溶胶凝胶法制备了钛基锡系阳极,且掺杂 Sb、La等元素对该电极材料进行了改性,并把该系列电极用于电化学处理模拟对硝基苯酚废水。通过SEM和XRD对电极形貌进行表征,分析了元素掺杂改善电极性能的机理,考察了电解条件对电化学降解对硝基苯酚效果的影响,探究了电场因素对电化学体系降解废水的影响机制。通过紫外吸收光谱分析推断了对硝基苯酚在电化学作用下可能的降解历程。研究结果表明:同时掺杂La和Sb的电极降解对硝基苯酚效果最好;在电解电压12 V、极板间距25 mm、pH值为7、电解质浓度0.5 mol/L的条件下电解120 min,对硝基苯酚的降解率可达92.8%,可见应用掺杂La、Sb的Ti/SnO2电极材料的电化学法降解对硝基苯酚优势相当明显。
In order to achieve the efficient degradation of nitro aromatic organic pollutants,a series of titanium based tin anodes were prepared in the treatment of simulated nitro phenol wastewater. Sb and La were selected as promoters in the electrode coating,and the degradation effects of different electrode materials were reviewed. The micrographs and structures of the electrodes were characterized by SEM and XRD. Element composition of electrode coating was determined by EDS. The effects of electrode surface properties on electrochemical degradation of organic pollutants were analyzed. The mechanism of improvement on the electrochemical performance of electrode materials by element doping was studied,and the optimal doping ratio of elements was determined. The effects of electrolytic parameters on p-nitrophenol degradation were also investigated. The influences of electric field on the electrochemical degradation of wastewater were analyzed The results showed that the electrocatalytic performance of the electrode doped with Sb and La was superior for the treatment of p-NP wastewater. Under the optimum electrolysis conditions with electrolysis voltage 12 V,plates distance 25 mm,pH7,electrolyte concentration 0.5 mol/L,the degradation rate of nitro phenol could reach 92.8%after 120 min.