Efficient and rapid capture of uranium(VI) in wastewater via multi-amine modified β-cyclodextrin porous polymer

It is quite important to ensure the safety and sustainable development of nuclear energy for the treatment of radioactive wastewater. To treat radioactive wastewater efficiently and rapidly, two multi-amine beta-cyclodextrin polymers (diethylenetriamine beta-cyclodextrin polymer (DETA-TFCDP) and triethylenetetramine beta-cyclodextrin polymer (TETA-TFCDP)) were prepared and applied to capture uranium. Results exhibited that DETA-TFCDP and TETA-TFCDP displayed the advantages of high adsorption amounts (612.2 and 628.2 mg.g(-1), respectively) and rapid adsorption rates, which can reach (88 +/- 1)% of their equilibrium adsorption amounts in 10 min. Moreover, the adsorbent processes of DETA-TFCDP and TETATFCDP on uranium(VI) followed the Langmuir model and pseudo-second-order model, stating they were mainly chemisorption and self-endothermic. Besides, TETA-TFCDP also showed excellent selectivity in the presence of seven competing cations and could be effectively reused five times via Na2CO3 as the desorption reagent. Meanwhile, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy illustrated that the enriched multi-amine groups and oxygen-containing functional groups on the surface of TETA-TFCDP were the main active sites for capturing uranium(VI). Hence, multi-amine beta-cyclodextrin polymers are a highly efficient, rapid, and promising adsorbent for capturing uranium(VI) from radioactive wastewater. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.