Research Center for Analytical Sciences, Tianjin Key Laboratory of Molecular Recognition and Biosensing, College of Chemistry , Nankai University , Tianjin 300071 , China.
State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Institute of Analytical Food Safety, School of Food Science and Technology , Jiangnan University , Wuxi 214122 , China.
Environ Sci Technol. 2019 May 7;53(9):5212-5220. doi: 10.1021/acs.est.8b06244. Epub 2019 Apr 10.
Capture of radioactive TcO from nuclear wastes is extremely desirable for waste disposal and environmental restoration. Here, we report the synthesis of hydrolytically stable cationic covalent organic nanosheets (iCON) for efficient uptake of ReO, a nonradioactive surrogate of TcO. The iCON combines cationic guanidine-based knots with hydroxyl anchored neutral edge units and chloride ions loosely bonded in the pores, rendering extremely fast exchange kinetics toward ReO with high uptake capacity of 437 mg g and prominent distribution coefficient of 5.0 × 10. The removal efficiency remains stable over a pH range of 3-12 and allows selective capture of ReO in the presence of excessive competing anions such as NO, CO, PO and SO with good removal efficiency for ReO in a simulated Hanford LAW Melter Recycle Stream. Anion exchange between the ReO in solution and the chloride ion in iCON plays dominant role in the adsorption of ReO. The iCON shows promise for effective removal of radioactive Tc from nuclear waste.
从核废料中捕获放射性 TcO 对于废物处理和环境修复是极其理想的。在这里，我们报告了水解稳定的阳离子共价有机纳米片（iCON）的合成，用于有效摄取 ReO，一种 TcO 的非放射性替代物。iCON 将基于胍的阳离子结与羟基锚定的中性边缘单元以及松散结合在孔中的氯离子结合在一起，对 ReO 表现出极快的交换动力学，具有 437mg/g 的高摄取容量和突出的分配系数 5.0×10。去除效率在 pH 值为 3-12 的范围内保持稳定，并允许在存在过量竞争阴离子（如 NO、CO、PO 和 SO）的情况下选择性地捕获 ReO，对模拟 Hanford LAW 玻璃化再循环料流中的 ReO 具有良好的去除效率。溶液中的 ReO 和 iCON 中的氯离子之间的阴离子交换在 ReO 的吸附中起主要作用。iCON 有望从核废料中有效去除放射性 Tc。
