State Key Laboratory for Nuclear Resources and Environment, East China University of Technology, 418 Guanglan Road, 330013 Nanchang, China.
State Key Laboratory for Nuclear Resources and Environment, East China University of Technology, 418 Guanglan Road, 330013 Nanchang, China; School of Chemical Sciences and Engineering, University of New South Wales, 2035 Sydney, Australia.
Int J Biol Macromol. 2022 Oct 1;218:190-201. doi: 10.1016/j.ijbiomac.2022.07.116. Epub 2022 Jul 21.
The development of new adsorbents is needed to address the environmental challenges of radioactive wastewater treatment. Herein we reported a novel polyethyleneimine incorporated chitosan/α-MnO nanorod honeycomb-like composite (PCM) foam with remarkable elasticity and ultralight property for U(VI) removal. Among different PCM sorbents, PCM-40 possessed the highest sorption capacity for U(VI) due to its highly developed macroporous structure and high content of amine/imine groups. The kinetics were well-simulated by the pseudo-second-order model, indicating chemisorption as the rate-controlling step. The isotherms could be described by the Langmuir model, suggesting mono-layer homogeneous sorption of U(VI). The maximum sorption U(VI) capacity for PCM-40 reaches up to 301.9 mg/g at pH 4.5 and 298 K. The thermodynamic parameters revealed the spontaneous and endothermic nature of the adsorption process. The main sorption mechanism is related to the complexation of uranyl ions with the amine/imine and hydroxyl groups. The high sorption capacity, fast kinetic rate and relatively good selectivity of PCM-40 highlights its promising application in radioactive pollution cleanup.
需要开发新型吸附剂来应对放射性废水处理的环境挑战。本文报道了一种具有显著弹性和超轻特性的新型聚乙烯亚胺结合壳聚糖/α-MnO 纳米棒蜂窝状复合材料（PCM）泡沫，用于去除 U(VI)。在不同的 PCM 吸附剂中，PCM-40 由于具有高度发达的大孔结构和高含量的胺/亚胺基团，对 U(VI)具有最高的吸附容量。动力学很好地通过拟二级模型进行模拟，表明吸附过程是化学控制步骤。等温线可以用 Langmuir 模型来描述，表明 U(VI)的单层均匀吸附。在 pH 4.5 和 298 K 下，PCM-40 的最大 U(VI)吸附容量达到 301.9 mg/g。热力学参数表明吸附过程是自发和吸热的。主要的吸附机制与铀酰离子与胺/亚胺和羟基的络合有关。PCM-40 具有高吸附容量、快速动力学速率和相对较好的选择性，突出了其在放射性污染清理中的应用前景。
