磁性离子印迹聚合物的功能调控及其对铀污染土壤的修复机制研究

The rapid development and application of the nuclear technology are fueling buoyant demand for uranium. There will be uranium accompanied radioactive contamination in soil of mining area. Uranium in soil has both chemical and radiological toxicity. On the one hand, remediation of the uranium contaminated soil is a prerequisite for decommissioning of uranium mines. On the other hand, uranium contaminated soil treatments have great social and ecological benefits. There are disadvantages for traditional soil washing using chemical solvent, such as difficult to recover the solvent, causing the secondary pollution in soil, and hard to deal with the water-treatment sludge. This project will use the micro and nano magnetic ion imprinted polymer (MIIP) instead of chemical solvent to wash the uranium contaminated soil. High gradient pulsating magnetic separator is used to separate the MIIP and soil. Several uranium contaminated soil samples in typical mines in the South, and North China will be collected. The main research objects of this project will be as follows: 1) Preparation and regulation of the micro or nano scale MIIP, 2) Research on the reaction mechanism between MIIP and the uranium in soil. The main research methods of this project will base on the theory of organic bonding, Interfacial adsorption theory and uranium/soil chemical mechanism. This project will discuss the following scientific questions: 1) Balance and regulation of particle size, activity, magnetism and stability of the MIIP, 2) The mechanism of MIIP destabilized the uranium in the solid liquid system of soil. A cleaning technology for uranium pollution in mine soil by MIIP will be developed. This project will also clarify the interaction mechanism of MIIP and uranium during the magnetic soil cleaning process. Therefore, this work will provide the theoretical basis for the treatment of contaminated soil in uranium mines. At the meantime, it will provide a novel technology for heavy metal contaminated soil cleaning.

核技术的广泛应用促使铀的需求猛增，铀在开采过程中不可避免地进入矿区土壤引起放射性污染。矿区污染土壤修复一方面是退役铀矿山合规闭矿的前提条件，另一方面具有较大的社会和生态效益。基于化学溶剂的传统土壤清洗不易再生药剂、易二次污染土壤、难于处置水处理污泥。本项目拟利用微纳米磁性离子印迹聚合物（MIIP）替代传统化学溶剂，通过磁选分离土壤和MIIP，实现土壤铀污染选择性去除同步资源化。本项目拟围绕MIIP制备调控及其与土壤中铀的作用机制展开研究，拟基于有机成键、界面吸附及土壤铀化学理论，研究MIIP的粒径、界面活性、磁性和稳定性平衡与调控，探索MIIP、清洗方式、土壤物理化学性质对不同存在形态铀清洗效率的影响规律等，针对南方和北方典型矿山铀污染土壤，形成MIIP清洗矿山土壤铀污染技术，阐明铀污染矿山土壤MIIP清洗去污机制，为铀矿山污染土壤治理提供理论依据，并为重金属污染土壤清洗提供新的技术选择。

核技术的广泛应用促使铀的需求猛增，铀在开采过程中不可避免地进入矿区土壤引起放射性污染。矿区污染土壤修复一方面是退役铀矿山合规闭矿的前提条件，另一方面具有较大的社会和生态效益。基于化学溶剂的传统土壤清洗不易再生药剂、易二次污染土壤、难于处置水处理污泥。本项目利用磁性羟基磷灰石M-HAP替代传统化学溶剂，通过磁选分离土壤和M-HAP，实现了土壤铀污染选择性去除。项目围绕M-HAP的制备调控及其与土壤中铀的作用机制展开研究，探索了磁性吸附材料、清洗方式、土壤物理化学性质对不同存在形态铀清洗效率的影响规律；形成了M-HAP清洗矿山土壤铀污染技术，阐明了铀污染矿山土壤M-HAP清洗去污机制；为铀矿山污染土壤治理提供理论依据，并为重金属污染土壤清洗提供新的技术选择。