地下水中无机砷污染赋存形态的电化学分析

Arsenic contamination in groundwater is a world-wide environmental problem. Identification of inorganic arsenic speciation in groundwater is one of the most challenging environmental issues. This project is based on the interdisciplinary study of environmental chemistry and electrochemical analytical chemistry. A gold ultramicro electrochemical electrode system has been designed and fabricated for qualitative and quantitative analysis of the two typical inorganic arsenic species (As (III) and As (V)) in the typical high arsenic groundwater at Togtoh, Inner Mongolia, China. Based on systematical research of the electrochemical behavior of the different species of inorganic arsenic in the typical high arsenic groundwater, this project devotes to achieve the following scientific goals: Firstly, elucidating the conversion process between the different forms of inorganic arsenic; Secondly, intensive understanding the mass diffusion and charge transfer process of different forms of inorganic arsenic on the gold ultramicro electrochemical electrode; Thirdly, revealing mechanism of the electrochemical behavior of inorganic arsenic with the interference of typical inorganic ions, and natural organic matter coexisting in the high arsenic groundwater. In sum, this project would provide theoretical and technical supports for developing the rapid, and on site analytical method for identification of inorganic arsenic speciation in the groundwater with high arsenic contamination.

地下水砷污染是世界性的环境问题，确定地下水中无机砷污染的赋存形态是环境研究中非常具有挑战性的研究领域之一。本项目将运用环境化学与电分析化学学科交叉，以内蒙古自治区呼和浩特市托克托县典型的高砷污染的地下水为研究对象，构筑超微金丝电化学电极体系对其中As(III)与As(V)两种典型的无机形态砷进行定性与定量分析。通过系统地研究典型高砷地下水中不同形态无机砷污染的电化学行为，致力于阐明不同形态无机砷之间的转换过程，明确超微金丝电化学电极上高砷地下水中共存的典型无机离子、天然有机物对不同形态无机砷污染的传质扩散与电荷转移过程的影响规律，从而为发展快速、现场高砷地下水中无机砷污染赋存形态分析手段提供理论基础和技术支撑。

地下水砷污染是世界性的环境问题，确定地下水中无机砷污染的赋存形态是环境研究中非常具有挑战性的研究领域之一。本项目主要构筑了针对地下水中无机形态砷的金丝微电极及纳米结构材料修饰电极体系，发展了针对实际地下水环境中无机形态砷的金丝微电极电化学定性与定量分析方法。首先，采用红外光谱、X射线光电子能谱分析以及同步辐射X射线吸收光谱等手段揭示了地下水中共存的无机离子和有机物质对砷电化学行为的影响规律，建立了实际地下水分析过程中常见干扰的消除方法；其次，发展了基于金属氧化物、金属氧化物/贵金属等纳米结构材料修饰电极实现在中性或近中性条件下对无机形态砷的电化学分析，拓宽了无机形态砷电化学分析方法的应用条件；此外，还发展了多种针对水环境中持久性有机污染物和其他重金属污染物的检测新方法。这些研究成果为水环境中无机形态砷等有毒污染物的分析提供了重要的理论参考与技术支撑。相关成果相关在Analytical Chemistry，Journal of Hazardous Materials, Sensors and Actuators B: Chemical等国际SCI期刊发表相关论文12篇，并获得2014年度中国分析测试协会科学技术奖二等奖，培养博士研究生3名，硕士研究生1名。