Interactions between copper(II) and DOM in the urban stormwater runoff: modeling and characterizations
Interactions between copper(II) and DOM in the urban stormwater runoff: modeling and characterizations
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DOI：
10.1080/09593330.2017.1296893
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发表时间：
2018-01
影响因子：
2.8
通讯作者：
Chen Zhao;Chongchen Wang;Jun-qi Li;Peng Wang;Jiangbo Ou;Jingna Cui
中科院分区：
文献类型：
--
作者：
Chen Zhao;Chongchen Wang;Jun-qi Li;Peng Wang;Jiangbo Ou;Jingna Cui
溶解性有机物（DOM）与有机和无机污染物相互作用，影响污染物的迁移、转化、生物利用度、毒性甚至最终命运。在这项工作中，DOM是从中国北京一个典型住宅区的常规采样点收集的城市雨水径流样本中提取的。选择铜（II）离子作为模型，研究DOM与典型重金属的相互作用。采用紫外（UV）吸光度法和荧光滴定法测定了DOM与铜离子的络合容量（CL）和条件稳定常数（log KM），结果表明，DOM与铜离子的络合容量（CL）和条件稳定常数（log KM）分别为85.62和87.23 μmol mg−1，对数KM分别为5.37和5.48。结果表明DOM与铜离子成功络合。此外，通过能量色散x射线能谱（EDX）和x射线光电子能谱（XPS）证实了DOM与铜（II）离子结合的形态，有助于阐明相应的机理。在XPS光谱中发现了Cu 2p3/2在933.7 eV处的峰和Cu - o的特征振荡峰，表明铜（II）离子可能与羟基（脂肪族或酚类）或羧基配位。这些有益的结果表明，城市雨水径流中的DOM与铜（II）离子具有较强的结合亲和力，这可能会对铜（II）离子的迁移和转化产生潜在的重大影响。
ABSTRACT Dissolved organic matter (DOM) can strongly interact with both organic and inorganic contaminants to influence their transportation, transformation, bioavailability, toxicity and even their ultimate fate. Within this work, DOM was extracted from urban stormwater runoff samples collected from a regular sampling site of a typical residential area in Beijing, China. Copper(II) ions were selected as model to investigate the interactions between DOM and typical heavy metals. Both ultraviolet (UV) absorbance and fluorescence titration methods were introduced to determine the complex capacities (CL) and conditional stability constants (log KM) of bonding between DOM and copper (II) ions, which revealed that the values of CL were 85.62 and 87.23 μmol mg−1 and the log KM values were 5.37 and 5.48, respectively. The results suggested the successful complexation between DOM and copper(II) ions. Furthermore, morphology of the DOM binding to copper(II) ions was confirmed by both energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS), which can facilitate to clarify the corresponding mechanism. The Cu 2p3/2 peak at 933.7 eV and the characteristic shake-up peaks of Cu–O were found in the XPS spectra, implying that copper(II) ions might coordinate with hydroxyl (aliphatic or phenolic) or carboxyl groups. With these profitable results, it can be concluded that DOM in urban stormwater runoff has a strong binding affinity with copper(II) ions, which may further lead to potentially significant influence on their migration and transformation.