易回收磷钼酸铵基高效Cs+捕集纳米复合材料的制备、表征与吸附机理

The utilization and development of nuclear energy is one of the most promising way to the enery crisis all over the world. Meanwhile, it also brings many threats to the environment and human beings. However, the technologies, theories and materials used to the treatment of nuclear pollutions are insufficient seriously now. Ammonium molybdophosphate (AMP) has been proven to be a good adsorbent for the removal of radiocesium. But it has certain defects, such as poor mechanical intensity and difficult to recovery, which limited its application. In this project, we will design and synthesize novel easy recovery AMP/graphene oxide(AMP/GO) nanocomposites and macroscopic adsorbents for removal of radioactive cesium in water. First, we will prepare a hierarchical structure nanocomposite (AMP@Fe3O4/GO), which could be recovered effectively from aqueous solution by a magnet. At first, we will anchor the Fe3O4 nanoparticles (NPs) onto the surface of GO. Then add surfactants and adjust the crucial factors to in situ controllable growth of the AMP nanocrystals on the surface of Fe3O4NPs. Subsequently, we will analyze the relationship between morphology structure and efficiency by changing the component, morphology and size. Finally, we will reveal the adsorption mechanism. Second, we will synthesize AMP nanocrystals on the surface of some three dimensional network channel macroscopic bulk materials by interface binding and assembling and develop easy recovery inorganic-organic macro-bulk materials for nuclear pollution treatment. Next, we will explore the principle of interface assembling and build technology system for efficient Cs+ elimination. If this project is carried out successfully, it will provide new ideas for new material development of nuclear pollution removal and promote the development of other polluton remediation technologies.

核能的开发利用是解决全球能源危机的重要途径，但也带来了潜在的环境核污染隐忧。目前核污染处理技术、理论和材料严重缺乏，本项目针对磷钼酸铵(AMP)纳米微晶机械强度差、难成型、难回收的问题，拟开展用于水体放射性铯净化的AMP基复合材料的制备和吸附特性及机理研究。第一，通过在大比表面的氧化石墨烯(GO)上原位锚定磁性Fe3O4纳米粒子，再引入表面活性剂模板，在纳米Fe3O4表面原位可控合成AMP纳米晶体层，制备可磁性回收的AMP@Fe3O4/GO多级复合材料，解析材料的组分、形貌对铯吸附能力影响的构效关系，揭示其吸附机理。第二，将AMP纳米晶与三维网状多孔道宏观体相材料进行界面复合与组装，合成易回收的无机—有机宏观体相核污染净化材料，探索其界面组装原理，构建易回收的高效铯离子净化技术。本项目可为核污染净化材料开发提供新思路，并推动其他环境污染修复技术的发展。

以0.3%的氯化钠为电离抑制剂，基于原子吸收（火焰）分光光度法建立了一种快速测定水中铯离子的方法；利用已有的磁铁- Fe3O4纳米粒子的人工合成、改性方法，运用界面诱导自组装技术成功制备了介孔磁性磷钼酸铵多面体纳米复合材料（mag-AMP, AMP/Fe3O4），用于高效快速净化水中的铯离子，并且Fe3O4 纳米粒子均匀地镶嵌于磷钼酸铵多面体晶体内部使得复合材料获得了较强的磁性，能够利用外加磁场实现在污染水体中的快速回收；利用纳米碳材料的超大比表面积及其稳定的物理/化学特性，将Fe3O4可控锚定在纳米碳材料表面，再通过改性设计制备了可磁性回收的AMP@Fe3O4/纳米碳多级结构复合材料(CNC，carbon nano-composite) AMP@Fe3O4/CNC，该材料制备简便，净化速率快；最后，将制得的纳米吸附剂与高分子聚合物复合，成功制备了选择性吸附铯的高效、操作简单、广适性的三维新型实用轻便型核污染净化材料。研究结果可为核污染净化材料开发提供新思路，并推动其他环境污染修复技术的发展。