基于光谱特征的多重金属离子与DOM结合特性  

Binding Characteristics Between DOM and Multiple Metal Ions:Based on Spectral Features

作　　者：胡斌[1,2] 陈婷[1,2] 张楠楠[3] 施玥 包天力 HU Bin;CHEN Ting;ZHANG Nannan;SHI Yue;BAO Tianli(Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education,Hohai University,Nanjing 210024,China;College of Environment,Hohai University,Nanjing 210024,China;Jiangsu Academy of Environmental Industry and Technology Corp.,Nanjing 210019,China;Jiangsu Suli Environmental Technology Company Limited,Nanjing 210019,China)

机构地区：[1]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,江苏南京210024 [2]河海大学环境学院,江苏南京210024 [3]江苏环保产业技术研究院股份公司,江苏南京210019 [4]江苏省苏力环境科技有限责任公司,江苏南京210019

出　　处：《环境科学与技术》2024年第3期119-126,共8页Environmental Science & Technology

基　　金：国家重点研发计划(2022YFC3202402);国家自然科学基金项目(42007342);中央高校科研基本业务费项目(B220202063)。

摘　　要：通过淬灭滴定实验,文章采用同步荧光光谱和傅里叶红外光谱(FTIR)结合二维相关光谱分析,探究Cu^(2+)和Cd^(2+)多重离子与溶解态有机质(DOM)结合特性。研究结果表明,(1)DOM与Cu^(2+)和Cd^(2+)结合稳定常数(lg KM)分别为4.75~5.18和3.71~4.12,Cu^(2+)与DOM的结合能力要强于Cd^(2+)。(2)Cd^(2+)浓度为0和100μmol/L时,DOM点位与Cu^(2+)的结合顺序均为430~500 nm>330~420 nm,且Cd^(2+)存在时Cu^(2+)与DOM的lg KM为4.56~4.95。对比结果表明Cd^(2+)的存在并未影响DOM点位与Cu^(2+)的结合顺序,但减弱了DOM与Cu^(2+)的结合能力。(3)FTIR结果表明,Cd^(2+)浓度为0和100μmol/L时DOM官能团与Cu^(2+)结合顺序依次为酚类C-O>酰胺N-H>酰胺C=O>羧基C=O>芳香族C-H>多糖C-O和酰胺N-H>酰胺C=O>酚类C-O>芳香族C-H>多糖C-O。Cd^(2+)与酚类C-O结合后影响了Cu^(2+)与DOM中酚类C-O和羧基C=O官能团的结合。水环境中多重金属离子共存时的生物有效性和生态风险应受到关注。In this study,synchronous fluorescence spectroscopy and Fourier transform infrared spectroscopy combined with two-dimensional correlation spectroscopy analyses were applied to investigate binding characteristics between dissolved organic matter(DOM)and multiple Cu^(2+)and Cd^(2+)through quenching titration experiments.The results suggested that the binding constant(lgKM)for Cu^(2+)and Cd^(2+)ranged from 4.75~5.18 and 3.71~4.12,respectively,indicating the stronger binding affinity with Cu^(2+)than Cd^(2+).The binding sequence to DOM for Cu^(2+)both were 430 nm~500 nm>330 nm~420 nm under 0 and 100μmol/L Cd^(2+),and the lgK_(M) for Cu^(2+)ranged from 4.56~4.95 in the presence of Cd^(2+).The comparative result showed that the presence of Cd^(2+)had no effect on the binding sequence,but attenuate the binding affinity between DOM and Cu^(2+).FTIR results showed that,the structural changes of DOM upon interaction with Cu^(2+)under 0 and 100μmol/L Cd^(2+)followed the order of phenolic C-O>amide N-H>amide C=O>carboxyl C=O>aromatic C-H>polysaccharides C-O and amide N-H>amide C=O>phenolic C-O>aromatic C-H>polysaccharides C-O,respectively.The phenolic C-O interacted with Cd^(2+)and then affect the interaction between Cu^(2+)and DOM functional groups,such as phenolic C-O and carboxyl C=O.The bioavailability and ecological risk of heavy metals should be pay close attention under co-existence of heavy metals in wa⁃ter environments.

关 键 词：荧光光谱 多重金属离子 有机质 傅里叶红外光谱 二维相关光谱分析 

分 类 号：X52[环境科学与工程—环境工程]