铀被誉为核工业的“粮食”，但我国铀资源却相当贫乏，因此迫切需要解决从强酸性乏燃料和含铀废水以及碱性海水中进行铀资源回收利用。然而大多数吸附剂因耐酸碱性、耐辐照稳定性较差而严重受限于上述应用。针对这一难题，本项目拟选择新兴耐酸碱较好的有机-框架材料（COFs）为研究对象，拟通过引入磺酸基团不仅达到进一步提高材料耐酸碱、耐辐照能力，同时提高材料对铀的选择性吸附能力；制备系列磺酸功能化且孔壁磺酸数目可调、孔径大小可调的COFs材料，探索他们在酸性、碱性溶液中铀的吸附和实际放射性废液以及海水中铀的提取；揭示材料在酸、碱条件下的铀吸附能力与磺酸功能化、孔壁上磺酸数目、以及孔径大小的关系，并从结构上明确磺酸与铀的配位方式，阐明整个吸附机理和相关构效关系；赛选出适用于乏燃料后处理流程中铀的分离纯化、酸性含铀废水和海水提铀的新材料和新方法，对核燃料循环过程中铀污染的治理和核能的清洁可持续发展具有重要意义。

Uranium is regarded as the "grain" of nuclear industry, but uranium resources in China are very scarce. Therefore, it is urgent to solve the problem of uranium recovery and utilization from strong acid spent fuel, waste water containing uranium and seawater. However, most adsorbents are severely restricted by these applications due to their weak acid and alkali resistance and poor radiation stability. In order to solve this problem, covalent organic framework (COF), a new porous material with good acid and alkali resistance, was chosen as the research object. And through the introduction of sulfonic groups the ability of acid-alkali resistance and radiation resistance was expected to be improved, while the selective adsorption ability of uranium was improved. We will also construct a series of sulfonic acid functionalized COFs) with adjustable pore size, and then explore the adsorption of uranium in acidic and alkaline solutions and the extraction of uranium from actual radioactive waste liquid and seawater, thus revealing the relationship between the adsorption ability of uranium and sulfonic acid functionalization, as well as the number of sulfonic acid on pore wall and pore size. Moreover, we can also structurally disclose the coordination mode between sulfonic acid and uranium, and the whole adsorption mechanism and structure-activity relationship. Based on these results, we can obtain the best COF material and related technique for the separation and purification of uranium in the reprocessing process of spent fuel, acid uranium-containing wastewater and seawater for uranium extraction, thereby providing a new solution for the treatment of uranium pollution during the nuclear fuel cycle and the clean and sustainable development of nuclear energy.