胺肟类材料吸附分离铀的机理研究及高效吸附材料的开发

Amidoxime-based materials are the most promising sorbents for the extraction of uranium. But their unsatisfactory performance prevents the sorbents from practical usage in the extraction of uranium from seawater or uranium-containing wastewater. Up to present, most studies to improve the performance of the materials have focused on the process of preparation and the determination of apparent adsorption properties, and very little research effort has been dedicated to the adsorption mechanism and the identification of functional groups of different adsorption properties. Thus, without help from fundamental understanding at molecular level, there is no notable breakthrough in preparing adsorption material for efficiently extraction uranium in last many years. The proposed project intends to investigate the adsorption mechanism of uranium on this kind of material, the functionalization reaction and the degradation mechanism of the functional material with advanced techniques such as XAFS, pH potential titration and calorimetric titration. With the guidance from the results of fundamental studies, advanced sorbent is to be synthesized and a conceptual process for the extraction of uranium from seawater or wastewater using adsorption method is expected to be presented. Finally, the proposed project aims to improve performance of amidoxime-based materials and make the techniques of extraction of uranium using absorption method more practical.

胺肟类材料是最有希望实用化的铀吸附功能材料。但该类材料性能仍不够理想，限制了海水提铀和吸附法处理铀矿废水等技术的实用性。到目前为止，提升材料性能的研究多集中在材料的制备条件优化及宏观吸附性能的测定等方面，对材料吸附分离铀过程中的基础化学问题研究较少。因此，并不能从分子水平对材料的开发提供指导，致使该类材料的性能已多年没有突破性提升。本项目拟通过X射线精细结构分析（XAFS）、pH电位滴定、量热滴定等先进技术手段，对该类材料与铀酰等金属离子的配位机理、材料合成的反应历程、材料应用过程中的降解机理等关键基础化学问题进行研究；然后在基础研究结果的指导下，开发更为高效的铀吸附功能材料；并在掌握所得材料吸附铀性能的基础上，提出吸附法提铀概念流程并进行验证。最终达到通过基础研究提高胺肟类材料性能，并将吸附法提铀进一步推向实用的目的。