功能化介孔分子筛纤维的静电纺制备及其铀吸附行为与机制

Uranium is an important nuclear fuel and strategic resources. Due to its great value, together with the threat to public safety and health, more and more attention has been paid to research on the treatment of uranium-bearing waste. Thus, the development of novel and efficient adsorption materials is of important practical significance. Mesoporous molecular sieve fibers with large surface area, uniform and tunable pore size (ca. 2–10 nm), rich chemical composition, easy to be functionalized modifications and recycle, etc., have potential applications in adsorption and separation. In this project, we intend to fabricate novel functionalized-mesoporous molecular sieve fibers with high adsorption properties to uranyl ion by combining the electrospinning and surface modification methods, such as post-synthesis grafting and co-condensation synthesis. The effect of the preparative variables on the morphology and microstructure of mesoporous molecular sieve fibers will be studied, and the functional parameters on the microstructure and surface physicochemical properties of fibers will be also discussed. Then the adsorption performance of uranyl ion on the functionalized-mesoporous molecular sieve fibers will be studied by combining the characterization of microstructure and static adsorption methods. Futher, the adsorption mechanism of functionalied-mesoporous molecular sieve fibers to uranyl ion will be elucidated by FT-IR, Raman and XPS, combined with adsorption kinetics and thermodynamic models. This proposal is expected to provide a theoretical guidance and experimental basis for studying the adsorption of uranium-bearing waste by using novel functionalied-mesoporous molecular sieve fibers.

铀是重要的核燃料和战略资源，含铀废水的处理日益受到广泛关注，开发新型、高效的吸附材料具有重要的现实意义。介孔分子筛纤维具有比表面积大、孔道尺寸可调、化学组成丰富、可功能化改性以及易于回收利用等优点，在吸附分离方面具有潜在的应用前景。本项目拟结合静电纺丝技术与共聚合、后接枝等功能化改性手段，制备和开发新型、高效的铀吸附功能化介孔分子筛纤维。重点研究介孔分子筛纤维的制备参数与纤维形貌、微观结构的关系；研究功能化参数对纤维微观结构、表面物理化学性质的影响；研究功能化介孔分子筛纤维对铀的吸附行为。通过FT-IR、Raman以及XPS等表征手段，结合吸附动力学、热力学模型，阐明功能化介孔分子筛纤维吸附铀的作用机制，为新型功能化介孔分子筛纤维应用于含铀废水处理提供理论指导和实验依据。

铀是重要的核燃料和战略资源，含铀废水的处理日益受到广泛关注，开发新型、高效的吸附材料具有重要的现实意义。介孔分子筛纤维具有比表面积大、孔道尺寸可调、化学组成丰富、可功能化改性以及易于回收利用等优点，在吸附分离方面具有潜在的应用前景。本项目中，利用静电纺丝技术结合后嫁接法或共缩聚法的功能化改性手段，制备和开发了几种功能化介孔分子筛纤维，并分别研究了它们对铀的吸附性能。结果表明，材料均具有介孔结构。介孔氧化硅纤维(SiO2-Fiber)及二乙基磷酰功能化的氧化硅纤维(P-SiO2-Fiber)具有立方(Im3m)的介孔孔道结构; 而二乙基磷酰功能化的PVA复合介孔氧化硅纤维(P-PVA/SiO2-Fiber)具有蠕虫形介孔孔道结构。所制备的纤维料均展示了较好的U(VI)吸附性能，充分显示了功能化介孔硅基纤维材料在乏燃料后处理中吸附分离U(VI)中的巨大应用潜力。