Surface protection method for the magnetic core using covalent organic framework shells and its application in As(Ⅲ)depth removal from acid wastewater

作     者：Wenjun Huang Haomiao Xu Xiaoshuang Liu Longlong Wang Shutang Li Leipeng Ji Zan Qu Naiqiang Yan Wenjun Huang;Haomiao Xu;Xiaoshuang Liu;Longlong Wang;Shutang Li;Leipeng Ji;Zan Qu;Naiqiang Yan

作者机构：School of Environmental Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Pollution Control and Ecological SecurityShanghai 200092China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2022年第34卷第5期

页      面：1-9页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 081704[工学-应用化学] 07[理学] 08[工学] 070304[理学-物理化学(含∶化学物理)] 0817[工学-化学工程与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 

基　　金：This work was partly supported by the National Key R&D Program of China(No.2017YFC0210500) the National Natural Science Foundation of China(Nos.21806105,and No.52070129) This study was also supported by the Startup Fund for Youngman Research at SJTU(No.19×100040083) 

主　　题：Arsenic ions Covalent Organic Framework Core-shell structure Surface protectionLayer Thickness 

摘      要：Fe_(3)O_(4)-based materials are widely used for magnetic separation from ***,they often suffer from Fe-leaching behavior under acidic conditions,decreasing their ac-tivity and limiting sustainable practical *** this study,covalent organic frame-works(COFs)were used as the shell to protect the Fe_(3)O_(4) core,and the Fe_(3)O_(4)@COF core-shell composites were synthesized for As(Ⅲ)removal from acid *** imine-linked COFs can in situ grow on the surface of the Fe_(3)O_(4) core layer by layer with[COFs/Fe_(3)O_(4)]mol ratio of up to 2∶*** Fe-leaching behavior was weakened over a wide pH range of ***,such composites keep their magnetic characteristic,making them favorable for nanomaterial ***(Ⅲ)batch adsorption experiments results indicated that,when COFs are used as the shell for the Fe_(3)O_(4) core,a balance between As(Ⅲ)removal efficiencies and the thickness of the COF shell *** As(Ⅲ)removal efficiencies are obtained when the[COFs/Fe_(3)O_(4)]mol ratios were1.5∶1,but thicker COF shells were not beneficial for As(Ⅲ)*** composites also exhibited better As(Ⅲ)removal performances in the pH range of *** a wide pH range,the zeta potential of Fe_(3)O_(4)@COF core-shell compos-ites becomes more positive,which benefits the capture of negative arsenic *** addition,thinner surface COFs were favorable for mass transfer and facilitating the reaction of Fe and As *** study highlights the promise of using COFs in nanomaterial surface protection and achieving As(Ⅲ)depth removal under acidic conditions.