Shen Nannan, Yang Zaixing, Liu Shengtang, Dai Xing, Xiao Chengliang, Taylor-Pashow Kathryn, Li Dien, Yang Chuang, Li Jie, Zhang Yugang, Zhang Mingxing, Zhou Ruhong, Chai Zhifang, Wang Shuao
State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China.
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
Nat Commun. 2020 Nov 4;11(1):5571. doi: 10.1038/s41467-020-19374-9.
Removal of TcO from legacy defense nuclear tank waste at Savannah River Site is highly desirable for the purpose of nuclear safety and environmental protection, but currently not achievable given the extreme conditions including high alkalinity, high ionic strength, and strong radiation field. Herein, we present a potential solution to this long-term issue by developing a two-dimensional cationic metal organic framework SCU-103, showing ultrahigh stability in alkaline aqueous media and great resistance to both β and γ radiation. More importantly, it is very effective for TcO separation from aqueous media as demonstrated by fast exchange kinetics, high sorption capacity, and superior selectivity, leading to the successful removal of TcO from actual Savannah River Site high level tank waste for the first time, to the best of our knowledge. In addition, the uptake mechanism is comprehensively elucidated by molecular dynamics simulation and density functional theory calculation, showing a unique chemical recognition of anions with low charge density.
从萨凡纳河工厂遗留的国防核罐废物中去除高锝酸盐（TcO）对于核安全和环境保护而言非常必要，但鉴于包括高碱度、高离子强度和强辐射场在内的极端条件，目前无法实现。在此，我们通过开发一种二维阳离子金属有机框架SCU-103，提出了一个解决这一长期问题的潜在方案，该框架在碱性水介质中表现出超高稳定性，并且对β和γ辐射都具有很强的抗性。更重要的是，它在从水介质中分离TcO方面非常有效，快速的交换动力学、高吸附容量和卓越的选择性证明了这一点，据我们所知，这首次成功地从萨凡纳河工厂实际的高放罐废物中去除了TcO。此外，通过分子动力学模拟和密度泛函理论计算全面阐明了吸附机制，显示出对低电荷密度阴离子的独特化学识别。
