BDD 和 PbO2电极电化学氧化苯并三氮唑的对比研究.pdf

第36卷第7期 环 境 科 学 Vol.36,No.7 2015年7月 ENVIRONMENTAL SCIENCE Jul. ,2015 BDD和PbO 电极电化学氧化苯并三氮唑的对比研究 2 伍娟丽,张佳维,王婷,倪晋仁﹡ (北京大学环境工程系,水沙科学教育部重点实验室,北京 100871) 摘要:分别构建了以掺硼金刚石膜电极(BDD)和二氧化铅电极(PbO )为阳极的电化学体系,对比考察了两种电极对难降解2 有机污染物苯并三氮唑(BTA)的降解及体系的矿化效果,并从电极产生羟基自由基(.OH)的数量与形态角度深入探讨了影 响电极矿化能力大小的内在因素. 结果表明:①BDD和PbO2 电极均对BTA有较好的降解效果,电解12 h后BTA去除率分别 为99.48℅和98.36℅,但BDD 电极的矿化能力明显强于PbO2 电极,电解12 h后矿化率分别为87.69℅和35.96℅;②BDD 体系阳极.OH产生速率和阴极H 产生速率均低于PbO 体系,即表面活性位点数量少于PbO 电极,因此.OH数量不是决定矿2 2 2 化能力大小的关键;③BDD 电极表面吸附氧活性更强,结合能(532.37eV)大于PbO (530.74eV),且表面吸附层更薄,产生的2 .OH形态更自由,是决定其具有更大矿化能力的关键因素. 关键词:掺硼金刚石;二氧化铅;羟基自由基;苯并三氮唑;活性位点;吸附氧;吸附层 中图分类号:X505 文献标识码:A 文章编号:0250-3301(2015)07-2540-07 DOI:10.13227/ j.hjkx.2015.07.029 ComparativeStudyofBenzotriazoleElectrochemicalOxidationatBoron-doped DiamondandPbO Anodes 2 WUJuan-li,ZHANGJia-wei,WANGTing,NI Jin-ren﹡ (The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University,Beijing 100871,China) Abstract:Electrochemical systemswere built to investigate the degradation of benzotriazole (BTA) on boron-doped diamond (BDD) and PbO2 anodes and give an insight into the mineralization ability of two electrodes in terms of the amount and activity of hydroxyl radicals. Results of bulk electrolysis showed that both BDD and PbO2 displayed perfect BTA degradation performance after 12 hours’ electrolysis,with the removal percentages of 99.48℅ and 98.36℅,respectively,while the mineralization ability of BDD was much stronger than that of PbO2 ,with the efficiency of 87.69℅ for BDD and 35.96℅ for PbO . Less hydroxyl radical and hydrogen2 production in BDD system suggested the less amount of active sites on BDD surface,thus further verified that the generated hydroxyl radical amount was not the