摘要
为提高电容去离子技术(CDI)对水中镉离子(Cd^(2+))的去除效率,以氧化石墨烯(GO)为主吸附材料、改性碳纳米管(CNT^(*))为次吸附材料兼导电剂制备了复合电极,通过测试比表面积、循环伏安特性曲线可知,当m(氧化石墨烯)∶m(碳纳米管)∶m(聚偏氟乙烯)=7.2∶0.8∶2时,电极的比表面积为391.72 m^(2)/g,比吸附量达到11.25 mg/g,比电容达到142.36 F/g。工作电压为1.2 V、循环流速为20 m L/min、电极板间距为3 mm、电极对数达到4对时,镉的去除率可以达到91.8%。通过动力学分析,准一级动力学模型能较好地描述电极对离子的吸附速率。通过对吸附等温线拟合分析,Langmuir模型的拟合率为98.9%,Freundlich模型的拟合率为99.87%,证明GO/CNT^(*)电极在CDI去除镉离子中具有较好的效果。
To improve the removal efficiency of Cd^(2+)in water through capacitive deionizing technology,a composite electrode is prepared by using modified graphene oxide(GO)as main adsorption material,and modified carbon nanotubes(CNT^(*))as secondary adsorption material and conductive agent.By detecting specific surface area and cyclic voltammetry characteristic curve,it is found as the mass ratio of m(GO)∶m(CNT^(*))∶m(polyvinylidene fluoride)=7.2∶0.8∶2,the composite electrode has a specific surface area of 391.72 m^(2)·g-1,a specific adsorption capacity of 11.25 mg·g-1 and a specific capacitance of 142.36 f·g-1.Cadmium ion removal rate can reach 91.8%when the working voltage is 1.2 V,the circulating flow rate is 20 ml·min-1,the electrode plate spacing is 3 mm,and the electrode logarithm reaches 4 pairs.Through kinetic analysis,quasi-first-order kinetic model can describe well the adsorption rate of the electrode to ions.By means of adsorption isotherm fitting analysis,it has a fitting rate of 98.9%to Langmuir model,and a fitting rate of 99.87%to Freundlich model.It proves that GO/CNT^(*)composite electrode has a good adsorption effect in removing cadmium ion by capacitive deionizing technology.
作者
余杨
王黎
鲁逸飞
胡雨莎
廖梦根
YU Yang;WANG Li;LU Yi-fei;HU Yu-sha;LIAO Meng-gen(School of Resources and Environment Engineering,Wuhan University of Science and Technology,Wuhan 430081,China)
出处
《现代化工》
CAS
CSCD
北大核心
2021年第6期134-139,共6页
Modern Chemical Industry
基金
湖北省国家自然科学基金(16CFA086)。
关键词
氧化石墨烯
碳纳米管
电容去离子
复合材料
镉离子
graphene oxide
carbon nanotubes
capacitive deionizing
composites
cadmium ion
