Design of ion-imprinted cellulose-based microspheres for selective recovery of uranyl ions

Nadia H Elsayed; M Monier; Raedah A S Alatawi; Menier Al-Anazi

doi:10.1016/j.carbpol.2023.120873

Design of ion-imprinted cellulose-based microspheres for selective recovery of uranyl ions

Carbohydr Polym. 2023 Aug 1:313:120873. doi: 10.1016/j.carbpol.2023.120873. Epub 2023 Apr 5.

Authors

Nadia H Elsayed¹, M Monier², Raedah A S Alatawi³, Menier Al-Anazi³

Affiliations

¹ 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. Electronic address: nhussein@ut.edu.sa.
² Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt. Electronic address: monierchem@yahoo.com.
³ Department of Chemistry, Faculty of Science, University of Tabuk, Tabuk 71421, Saudi Arabia.

PMID: 37182933
DOI: 10.1016/j.carbpol.2023.120873

Abstract

Herein, cellulose was selected as the raw material for the production of sorbent microspheres for the selective separation of uranyl (UO₂²⁺) 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 UO₂²⁺, crosslinking the UO₂²⁺ 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 UO₂²⁺-imprinting process, resulting in a much greater adsorption capacity of 382 ± 1 mg/g and enhanced adsorption selectivity for UO₂²⁺. 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 UO₂²⁺ chelation. The coordination between UO₂²⁺ and both the -NH₂ and -OH groups of the amidoxime units is the primary adsorption process, as shown by NMR, XPS, and FTIR studies. For UO₂²⁺ biosorption from aqueous effluents, the results of this study deliver new guidance for the design of biosorbents with high removal capability and excellent selectivity.

Keywords: Cellulose; Ion-imprinting; Uranyl ions.