2,6-二氨基蒽醌/石墨烯复合电极强化电吸附Pb2+  

Intensified Electrosorption of Pb2+ by 2,6-diaminoanthraquinone/Graphene Composite Electrode

作　　者：晋圣珧 向阳[1] 张隽瑀 张凯[3] 吉庆华 JIN Sheng-yao;XIANG Yang;ZHANG Jun-yu;ZHANG Kai;JI Qing-hua(College of Chemical Engineering,Beijing University of Chemical Technology,Beijing 100029,China;Center for Water and Ecology,Tsinghua University,Beijing 100084,China;Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)

机构地区：[1]北京化工大学化学工程学院,北京100029 [2]清华大学水质与水生态研究中心,北京100084 [3]中国科学院生态环境研究中心,北京100085

出　　处：《环境科学》2019年第9期4091-4097,共7页Environmental Science

基　　金：国家自然科学基金项目(51608516);国家水体污染控制与治理科技重大专项(2017ZX07202003)

摘　　要：电吸附高效去除水中重金属离子的关键在于开发性能优异的电极材料.采用2,6-二氨基蒽醌(DA)修饰还原氧化石墨烯(rGO),通过溶剂热法成功制备了DA@rGO复合电极,考察了复合电极的电化学性质及电吸附Pb^2+性能.循环伏安测试表明,复合电极电化学性质优异,比电容在电流密度为1A·g^-1时达到304.4F·g^-1,DA修饰显著提高了复合电极的赝电容.电吸附Pb^2+测试表明,施加电压为-1.2V时电吸附效果最优,反应60min后Pb^2+去除率达94.8%.电吸附过程符合一级动力学方程,Langmuir模型拟合得到Pb^2+的饱和吸附量为356.66mg·g^-1,明显高于rGO电极(319.40mg·g^-1),DA修饰引起的电容增加是复合电极Pb^2+吸附量提高的重要原因.使用0.5mol·L^-1硝酸处理可使电极吸附的Pb^2+在5min内脱附完全,实现吸附剂再生.经过10次电极吸附-脱附循环后,DA@rGO复合电极对Pb^2+的吸附去除率保持在88%左右,电极循环性能稳定.The key to efficient removal of heavy metal ions from water by electrosorption is to develop electrode materials with excellent performance.In this study,2,6-diaminoanthraquinone (DA)-modified reduced graphene oxide (rGO) was used to prepare a DA@rGO composite electrode using the solvothermal method.The electrochemical properties,electrosorption of Pb^2+,adsorption kinetics,and cycle regeneration performance of the composite electrode were investigated.Cyclic voltammetry showed that the composite electrode had excellent electrochemical properties,and the specific capacitance reached 304.4 F·g^-1 at a current density of 1 A·g^-1.The DA modification significantly increased the pseudocapacitance of the composite electrode.The electrosorption Pb^2+ test showed that optimal electrosorption was achieved with-1.2 V of the applied voltage,and the removal rate of the Pb^2+ reached 94.8% after 60 min.The electrosorption process is in accord with the first-order kinetic equation.The saturated adsorption capacity of Pb^2+ obtained by the Langmuir model was 356.66 mg·g^-1,which is significantly higher than that of rGO electrode,at 319.40 mg·g^-1.The increase in Pb^2+ adsorption amount of the composite electrode can be attributed to the increase in capacitance caused by DA modification.Treatment with 0.5 mol·L^-1 nitric acid can desorb the Pb^2+ within 5 min to achieve regeneration of the composite electrode.After 10 adsorption-desorption cycles,the adsorption removal rate of Pb^2+ by the composite electrode was kept at 88%, indicating robust stability.

关 键 词：2 6-二氨基蒽醌 还原氧化石墨烯 复合电极 电吸附 铅离子(Pb^2+) 

分 类 号：X703.1[环境科学与工程—环境工程]