柠檬酸配体促进Cu/Fe^(0)电子转移增强氧化性能的研究  

Mechanistic Study on the Degradation of Norfloxacin by Modified Zero-valent Iron Materials

作　　者：周曼[1,2] 卢瑶 孙辰 龚建宇 ZHOU Man;LU Yao;SUN Chen;GONG Jianyu(School of Environmental Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Hubei Electromechanical Research Institute Co.Ltd.,Wuhan 430070,China;Wuhan Science and Technology Center of Ecology and Environment,Wuhan 430070,China)

机构地区：[1]华中科技大学环境科学与工程学院,湖北武汉430074 [2]湖北省机电研究设计院股份公司,湖北武汉430070 [3]武汉市生态环境科技中心,湖北武汉430070

出　　处：《环境科学与技术》2022年第8期1-8,共8页Environmental Science & Technology

基　　金：国家重点研发计划(2020YFC1908702)。

摘　　要：该研究通过掺杂过渡金属Cu和Ni方式制备了2种改性纳米零价铁材料,在有无柠檬酸(CA)2种体系下,探究了材料对诺氟沙星的降解效果并分析其作用机理。结果表明,1%Cu/Fe^(0)-CA对诺氟沙星有最佳降解效果,1 h降解效率约为73%;而没有柠檬酸的Cu/Fe^(0)体系,也有70%左右的降解效率。结合DFT理论计算分析,对体系中·O_(2)^(-)、H_(2)O_(2)、·OH等自由基形成过程探究表明,无柠檬酸配体时主要是还原降解过程,在Fe^(0)转化Fe^(2+)时,电子直接传递至铁表面吸附的诺氟沙星,且还原氢(H*)起到还原作用。在有柠檬酸配体存在时则源于活化分子氧过程,在电子传递过程中产生H_(2)O_(2),继而与柠檬酸亚铁产生类Fenton反应,体现出强氧化效应。In this study,two modified zero-valent iron nanomaterials were prepared by doping with transition metals Cu and Ni,respectively,and the degradation effect and mechanism of the materials on norfloxacin were investigated in both systems with and without citric acid.The results showed that the 1%Cu/Fe^(0)-CA nanoparticles combined with citric acid performed the best degradation effect on norfloxacin,achieving 73% of degradation efficiency in 1 h;in the absence of the citric acid system,norfloxacin also had a 1 h degradation efficiency of about 70%.Combined with DFT theoretical calculation and analysis,further exploration of·O_(2)^(-)、H_(2)O_(2)and·OH shows that the absence of citric acid ligand is mainly a reduction degradation process.When Fe^(0)is converted to Fe^(2+),electrons are directly transferred to norfloxacin adsorbed on iron surface,and H*also plays a reducing role.In the presence of citric acid ligand,H_(2)O_(2) is generated in the process of electron transfer,and then Fenton-like reaction with ferrous citrate is produced,reflecting strong oxidation effect.

关 键 词：改性零价铁 柠檬酸 分子氧活化 活性氧基团 诺氟沙星 

分 类 号：X787[环境科学与工程—环境工程]