基于离子印迹技术选择性提取盐湖中Li+的材料体系构筑与机理研究

Ion imprinted adsorbents are designed and synthesized on the hybrid surface of carbon microspheres-graphene oxides (CMSs-GOs) for the efficient separation of Li+ from salt lake brine. Binding sites and imprinted cavities provide the selective recognition of Li+. Rapid mass transfer and efficient separation are realized by constructing the CMSs-GOs hybrid..First, imprinted matrix and recognition sites are designed and regulated by using the computer simulation technique to guide the synthesis of the imprinted materials. Then, CMSs and GOs are prepared by chemical vapor deposition, solvothermal method and chemical stripping method. The CMSs-GOs hybrid is constructed by self-assembly. Ion imprinted layer is prepared on the surface of CMSs-GOs hybrid by using Li+ as the target ion. The morphology and structure of samples at different stages are characterized and analyzed. The recognition and capturing performance of ion imprinted materials towards Li+ in salt lake brine are evaluated to reveal the recognition mechanism. Finally, surface ion imprinted materials with selective recognition are obtained for separating efficiently Li+ from salt lake brine. This project provides theoretical and technical basis for lithium extraction.

为解决盐湖中Li+的高效分离问题，本项目设计合成一种碳微球-氧化石墨烯（CMSs-GOs）杂化体系表面离子印迹型吸附分离材料。利用印迹聚合物丰富的网络结构提供与Li+匹配的结合位点和空穴，实现Li+的大容量、高选择性识别吸附；通过构建CMSs-GOs杂化体系骨架，实现Li+的快速传质和高效分离。.首先采用理论计算指导印迹体系中基体骨架与识别位点的设计与调控；然后通过化学气相沉积、溶剂热法、氧化剥离等技术获得CMSs和GOs等功能碳材料，并采用自组装法构建CMSs-GOs杂化体系；以Li+为目标离子，碳材料表面化学反应为手段，在CMSs-GOs基体骨架表面制备印迹聚合物层，并对各阶段产物的形貌和结构进行表征分析；系统探索材料在盐湖体系中的离子识别行为，揭示体系结构与识别性能的关系。最终获得具有选择性识别吸附与高效分离Li+的表面离子印迹材料，为实现盐湖高效提取和分离锂资源提供理论和技术基础。

锂及其化合物在航天和能源方面具有重要的战略意义。为解决盐湖中锂的高效分离问题，本项目设计合成一种碳微球-氧化石墨烯（CMSs-GOs）杂化体系表面离子印迹型吸附分离材料。主要内容包括：（1）采用不同碳球与石墨烯为组装单元，通过液相自组装法构建了三种CMSs-GOs杂化体系，经过对各产物结构与性能进行测试评价，确定氮掺杂碳微球-石墨烯NCMSs-GOs为优选载体。（2）以NCMSs-GOs为载体，苯并-12-冠-4醚为捕获剂，吡咯为功能单体，通过电控离子交换技术制备NCMSs-GOs杂化体系表面锂离子印迹材料，并对其结构与吸附性能进行评价，结果表明印迹材料对锂离子的吸附容量达到最大值50.62 mg/g，且具有良好的选择性和再生性。本项目的实施，为盐湖中锂的高效分离提供了新的思路和途径。