Department of Chemistry, Faculty of Science, University of Tabuk, Tabuk 71421, Saudi Arabia; Department of Polymers and Pigments, National Research Centre, Dokki, Cairo 12311, Egypt.
Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt.
Carbohydr Polym. 2023 Aug 1;313:120873. doi: 10.1016/j.carbpol.2023.120873. Epub 2023 Apr 5.
Herein, cellulose was selected as the raw material for the production of sorbent microspheres for the selective separation of uranyl (UO) ions by ion-imprinting technique due to their low cost, biodegradability, and renewability. To begin, an amidoxime cellulosic derivative (AOCE) is synthesized by a Michael addition followed by an amidoximation reaction, both of which are homogeneous reactions. In the end, microspheres of ion-imprinted U-AOCE sorbent were made by mixing the developed AOCE derivative with UO, crosslinking the UO polymer complex with glyoxal, and eluting the coordinated ions with H/EDTA. U-AOCE smartly recognized the target ions for fitting the cavities generated during the UO-imprinting process, resulting in a much greater adsorption capacity of 382 ± 1 mg/g and enhanced adsorption selectivity for UO. A pseudo-second-order model fit the data well in terms of kinetics, while the Langmuir model adequately explained the isotherms, indicating chemisorption and adsorption via UO chelation. The coordination between UO and both the -NH and -OH groups of the amidoxime units is the primary adsorption process, as shown by NMR, XPS, and FTIR studies. For UO biosorption from aqueous effluents, the results of this study deliver new guidance for the design of biosorbents with high removal capability and excellent selectivity.
在此，纤维素被选为生产吸附微球的原料，通过离子印迹技术对铀酰 (UO) 离子进行选择性分离，因为纤维素具有成本低、可生物降解和可再生的特点。首先，通过迈克尔加成反应和随后的羟胺化反应合成偕胺肟纤维素衍生物 (AOCE)，这两种反应都是均相反应。最后，通过将开发的 AOCE 衍生物与 UO 混合、用乙二醛交联 UO 聚合物配合物以及用 H/EDTA 洗脱配位离子，制备出离子印迹 U-AOCE 吸附剂微球。U-AOCE 智能地识别目标离子以适应 UO 印迹过程中产生的空腔，从而实现了 382±1mg/g 的更大吸附容量和对 UO 的增强吸附选择性。准二级动力学模型很好地拟合了动力学数据，而 Langmuir 模型则充分解释了等温线，表明通过 UO 螯合发生了化学吸附和吸附。NMR、XPS 和 FTIR 研究表明，UO 与偕胺肟单元的-NH 和-OH 基团之间的配位是主要的吸附过程。对于从水废水中吸附 UO，本研究的结果为设计具有高去除能力和优异选择性的生物吸附剂提供了新的指导。
