4.7 Article

FT-IR and synchronous fluorescence two-dimensional correlation spectroscopic analysis on the binding properties of mercury onto humic acids as influenced by pH modification and sulfide addition

期刊

SCIENCE OF THE TOTAL ENVIRONMENT
卷 819, 期 -, 页码 -

出版社

ELSEVIER
DOI: 10.1016/j.scitotenv.2021.152047

关键词

Binding properties; Mercury (Hg); DOM; 2D-COS; Sulfide addition

资金

  1. National Natural Science Foundation of China [21806140, 51908499]
  2. China Postdoctoral Science Foundation [2019M662105, 2021T140610]
  3. Natural Science Foundation of Zhejiang Province [LY20B070010, 2017129004429]
  4. Zhejiang University of Technology, China

向作者/读者索取更多资源

This study investigated the influences of pH and sulfide addition on the molecular structure of Hg2+-DOM complexes and the characteristics of Hg2+ binding to DOM using FTIR and synchronous fluorescence two-dimensional correlation spectroscopic analysis. The results showed that different functional groups in DOM exhibited different responses to Hg2+ binding. The formation of S-HA enhanced the binding ability of Hg2+ to DOM, with protein-like fractions playing a leading role in the binding process.
Mercuric Hg2+ ion forms strong complexes with dissolved organic matter (DOM) in natural waters. The complexation of Hg2+ by sulfhydryl groups of DOM was regarded as the main mechanism for Hg2+-DOM interactions, particularly in anoxic sulfur and DOM-rich environments. In the present study, the influences of pH and sulfide addition on the molecular structure of Hg2+-DOM complexes and the characteristics of Hg2+ binding to DOM were investigated using FTIR and synchronous fluorescence two-dimensional correlation spectroscopic analysis. Results showed that, during the Hg2+ binding process, the aromatic hydrogen CH in humic acids (HA) gave the fastest responses to pH perturbation and the S-reacted HA (S-HA) exhibited different reaction patterns from the unreacted HA. In S-HA, the esters/alcohols CO and carboxyl CO gave the fastest responses to Hg2+ binding. In the process of S-HA binding to Hg2+, the protein like fractions including proteins, amino acids or monoaromatics played the leading role. Sulfide addition of HA enhanced the reactivity of small molecular weight compounds with low aromaticity and improved the binding ability of protein-like fractions to Hg2+. These findings provide a better understanding of the interaction mechanisms between Hg2+ and DOM at a molecular level and have important environmental implications in Hg2+ biogeochemical transformation, transport and cycling.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据