等离子体技术可控制备亲水性聚偕胺肟/聚乙烯纤维材料及其海水提铀性能研究

Uranium is one fundamental material of nuclear energy. The known uranium reserves are limited and restricted to just several land resources of the world. > 99% of global uranium exists as U(VI) in seawater with an average concentration of ~3.0 μg/L. The development of sorbents with ideal selective enrichment for U(VI) plays a significant role in the long term dependable of uranium supply. Poly(amidoxime)/polyethylene (PAO/PE) is the typical adsorbent used for extraction uranium from seawater. In this project, hydrophilic monomers acrylic acid (AA), vinyl alcohol (VA), and acrylamide monomer (AAM) are selected as the sources of carboxyl, hydroxyl and amide groups to study the effect of hydrophilic groups on the adsorption capability of PAO/PE for U(VI). PAO/PE is prepared by plasma induced copolymerization of acrylonitrile and hydrophilic monomers (AA, VA, AAM), followed by amidoximation. The PAO/PE will be characterized by different analysis techniques. The adsorption behavior, chemical speciation, and micro geometric structure of U(VI) on PAO/PE will be studied by batch adsorption method and EXAFS technique. Batch adsorption method is used to study the adsorption behavior of U(VI) at different solution conditions (such as solution pH, ionic strength, and reaction temperature) in details; the regeneration–reused of PAO/PE is processed by eluting U–laden PAO/PE with different elutriant; EXAFS technique is employed to study the chemical speciation and micro geometric structure of U(VI) species adsorbed on PAO/PE surface; related chemical software is employed to simulate the experimental data and characterization results to clarify the stable configuration and adsorption mechanisms of U(VI) in molecular level. The prospective findings from this project will have great scientific significance for the development of efficient adsorbent for extraction of U(VI) from seawater in near future.

发展经济实用的海水提铀材料是关系我国未来战略安全和核能健康发展的重大课题。吸附法被认为是最适宜的海水提铀方法之一。本项目利用低温等离子体技术在聚乙烯表面一步共聚上丙烯腈和亲水性单体，然后进行偕胺肟化处理，可控制备具有不同官能团组成和形貌的亲水性聚偕胺肟/聚乙烯(PAO/PE)材料，并对该材料的微观性质进行表征分析；采用静态批实验技术研究PAO/PE材料对铀的吸附性能与规律，采用海试验证实验研究PAO/PE材料对真实海水中铀的吸附性能，采用淋洗剂淋洗技术研究PAO/PE材料的再生-重复利用性能，利用相关化学软件对实验数据进行数值模拟和计算，结合材料微观表征结果，揭示PAO/PE材料制备条件、形貌、表面官能团构成、吸铀性能之间的内在联系，推导U(VI)在PAO/PE材料上的稳定构型和吸附机理，阐明PAO/PE材料表面官能团的作用机制。本项目的开展，将为发展高效海水提铀材料提供参考依据。

发展经济实用的海水提铀材料是关系我国未来战略安全和核能健康发展的重大课题。针对海水提铀未来发展需求，本项目计划采用等离子体技术对PAO基纤维材料表面官能团类型与结构进行设计，发展了多种对铀具有高选择性富集作用的亲水性PAO/聚乙烯纤维复合材料；获得了该材料主要物理-化学行为特性、吸铀性能与机理、以及主要环境因素的影响。研究结果表明，PAO基海水提铀材料的亲水性和海水提铀性能与其表面官能团紧密相关，等离子体技术可以便捷地完成PAO基材料表面官能团的特定功能化修饰，进而有效提升其亲水性和海水提铀性能。研究结果将为有效提升我国海水提铀材料的性能提供有效参考依据。在基金的支持下，项目成员在国际SCI刊物上公开发表论文14篇，其中本人为第一/通讯作者论文为8篇，第一资助论文为6篇。研究结果受到国内外同行的广泛关注，被国内外同行正面引用300余次。项目培养了2名博士生和4名硕士生。