土壤氧化物表面铅吸附形态模拟与应用

项目名称： 土壤氧化物表面铅吸附形态模拟与应用

项目编号： No.41201231

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 地理学

项目作者： 汪明霞

作者单位： 华中农业大学

项目金额： 25万元

中文摘要： 重金属的毒性与其化学形态密切相关，而化学形态模型可用来计算和预测元素的化学形态和分布，揭示其物理化学过程的本质和重要影响因素。本项目以不同类型的铁/锰氧化物和受Pb污染严重的土壤为材料，通过分析和表征氧化物的晶体结构和表面电荷性质，分析单一氧化物、混合氧化物多界面吸附Pb的特点及其影响因素，利用分子环境手段和界面电化学方法研究Pb在氧化物表面结合机制，优化改善不同类型氧化铁吸附铅的相关参数，构建氧化锰矿物表面Pb吸附形态的化学模型；探讨混合氧化物多界面吸附Pb的特性，明确Pb的形态预测与实测数据偏离的物理化学原因，发展和完善能适用于不同类型氧化物表面铅形态分布的CD-MUSIC模型，并将其应用到Pb污染土壤形态分布与预测的计算。本项目的开展不仅可明确土壤多组分体系间相互作用对重金属离子分布因素和过程的影响，发展土壤与环境化学的模型，还可填补国内该领域研究的不足。

中文关键词： CD-MUSIC 模型；氧化物；形态分布；铅；表面电荷

英文摘要： The toxicity of heavy metals depends on their chemical speciation. Some chemical models can calculate the elemental speciation and distribution, and unravel the essence of its physical and chemical process and important factors. In this project, different types of iron and manganese oxide, and serious Pb contaminated soil as materials will be used. The crystalline structure and surface charge characterization of synthetic oxides will be obtained. Pb adsorption to single oxide, mixed oxide interfaces will be studied under different pH and ionic strength. The binding mechanism between oxides and Pb will be investigated by using molecular environment detection approaches and interfacial electrochemistry methods. The parameters of Pb adsorption on different iron oxides will be optimized, that of Pb adsorption on manganese oxides will be proposed, then Pb adsorption to multi-interfacial oxides will be developed. The discrepancy between the model prediction and measured distribution of Pb will be clarified. Finally, the developed CD-MUSIC model on different oxides will be applied to simulate Pb distribution in the natural Pb contaminated soil. This project will promote our understanding of the effect of soil interaction between multi-components system on heavy metal ions distribution factors and process, and to stimul

英文关键词： CD-MUSIC model；oxide；speciation distribution；lead；surface charge