摘要
工厂化养殖尾水中硝酸盐污染问题日益严重,而电化学还原技术中铜作为阴极材料去除NO_(3)^(-)-N存在活性位点少和吸附能力差的问题.为此采用一种具有高长径比(120)的Cu(OH)_(2)纳米线/Cu网电极材料应用于NO_(3)^(-)-N的电催化还原.首先,通过调控阳极氧化条件制备了Cu(OH)_(2)纳米线/Cu网.然后,通过对Cu(OH)_(2)纳米线/Cu网进行表征分析和去除NO_(3)^(-)-N性能测试,确定25℃、1.0 mol/L NaOH和2.0 mA/cm 2为Cu(OH)_(2)纳米线/Cu网最佳阳极氧化条件.在双池隔膜反应器中,以该电极为阴极,RuO_(2)-IrO_(2)-TiO_(2)/Ti为阳极,对NO_(3)^(-)-N(50 mg/L)去除率达到98%,NO_(3)^(-)-N还原速率达到0.0111 min-1/cm 2,是相同实验条件下未处理铜电极还原速率的6.5倍.最后,为了实现总氮(TN)去除,采用单池反应器,向体系中加1.0 g/L的氯离子将阴极产生的氨氮进一步转化为氮气,总氮去除率达到91%.循环实验结果显示该电极具有良好的稳定性,并且将该电极应用到实际水中NO_(3)^(-)-N的去除,总氮去除率达到92%.
Nitrate pollution in factory aquaculture tail water is increasingly serious.In electrochemical reduction technology,copper as cathode material for NO_(3)^(-)-N removal has the problems of few active sites and poor adsorption capacity.So Cu(OH)_(2)nanowire/Cu mesh electrode material with high length-to-diameter ratio(120)is proposed for the electrocatalytic reduction of NO_(3)^(-)-N.Firstly,the Cu(OH)_(2)nanowire/Cu mesh is prepared by adjusting the anodizing conditions.Then,through the characterization and analysis of Cu(OH)_(2)nanowire/Cu mesh and the evaluation of NO_(3)^(-)-N removal performance,the optimal anodizing conditions for Cu(OH)_(2)nanowire/Cu mesh are determined to be 25℃,1.0 mol/L NaOH and 2.0 mA/cm 2.With this electrode as the cathode and RuO_(2)-IrO_(2)-TiO_(2)/Ti as the anode,the removal rate of NO_(3)^(-)-N(50 mg/L)reaches 98%in the double-diaphragm reactor.The NO_(3)^(-)-N reduction rate of the cathode material reaches 0.0111 min-1/cm 2,which is 6.5 times that of the untreated copper electrode under the same conditions.Finally,in order to achieve total nitrogen(TN)removal,1.0 g/L chloride ion is used to further convert the ammonia nitrogen produced by the cathode into nitrogen in a single cell reactor,and the total nitrogen removal rate reaches 91%.The results of cycling experiments show that the electrode has good stability,and the electrode is applied to the removal of NO_(3)^(-)-N in actual water,the total nitrogen removal rate reaches 92%.
作者
徐腾遥
于洪涛
康文达
顾雨薇
XU Tengyao;YU Hongtao;KANG Wenda;GU Yuwei(School of Environmental Science and Technology,Dalian University of Technology,Dalian 116024,China)
出处
《大连理工大学学报》
CAS
CSCD
北大核心
2023年第5期463-471,共9页
Journal of Dalian University of Technology
基金
国家自然科学基金资助项目(21876021).
