Complexion between mercury and humic substances from different landfill stabilization processes and its implication for the environment
Complexion between mercury and humic substances from different landfill stabilization processes and its implication for the environment
复制标题
不同垃圾填埋场稳定过程中汞与腐殖质的络合及其对环境的影响
DOI：
10.1016/j.jhazmat.2011.12.077
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发表时间：
2012-03-30
影响因子：
13.6
通讯作者：
Zhao Youcai
中科院分区：
文献类型：
--
作者：
Chai Xiaoli;Liu Guixiang;Zhao Youcai
Three-dimensional excitation emission matrix (EEM) fluorescence spectroscopy was employed to investigate the structural properties and Hg(II)-binding behavior of humic substances (HS) extracted from different landfill stabilization processes. The EEM fluorescence properties of humic acid (HA) are characterized by intense fluorescence at Ex/Em = 440/500 nm and Ex/Em = 380/460 nm. Two relatively strong fluorescence peaks appeared in the region of Ex/Em = 260-290/350-370 nm with the landfill time extended, which represented a protein-like or soluble microbial byproduct structure. The fluorescence EEM spectrum of fulvic acid (FA) featured a prominent peak of strong relative fluorescence intensity (Fl= 1598) at Ex/Em = 330/440 nm (peak C) accompanied by a weak fluorophore (Fl = 594) located at Ex/Em = 275/445 nm (peak D). There were strong interactions between HA and Hg, and the overall stability constant of Hg(II)-HA was mainly determined by the abundant O-ligands existing in HA. FA had a much higher Hg(II)-complexing capacity compared to HA samples, which may be ascribed to its relatively high content of carboxylic groups. The Hg(II)-complexing capacity of HA tended to decrease with stabilization process extension. The much higher Hg(II)-complexing capacity of FA than that of HA implied that FA played an important role in binding Hg(II) in early landfill stabilization process. (C) 2012 Elsevier B.V. All rights reserved.
