High-Performance Engineered ZIF-67@PES Beads for Uranium Extraction from Aqueous Solutions

Abstract

This study presents the synthesis and performance evaluation of zeolitic imidazolate framework-67 (ZIF-67) polymer composites for uranium removal from aqueous solutions. The composites were synthesized by embedding ZIF-67 into poly(ether sulfone) (PES) beads via a phase inversion technique, yielding ZIF-67@PES beads. These beads are engineered for practical application in various aqueous streams, offering enhanced stability, reusability, and ease of operation. Furthermore, the uranium sorption capacity of the ZIF-67@PES composite was systematically evaluated under various physical conditions. The study examined the pH effect and equilibration time effect on uranium sorption, revealing that the beads achieved over 90% sorption efficiency within a pH of 3–7, and optimum sorption was achieved at pH 6, aligning with the pH of most natural water bodies. Kinetic analysis revealed that equilibrium was achieved within 90 min. The Langmuir isotherm model revealed a maximum uranium adsorption capacity of 83.26 mg U/g of the sorbent. ZIF-67@PES beads exhibited a superior performance compared to several previously reported sorbents, effectively removing uranyl ions while mitigating the effects of competing ions, underscoring their suitability for seawater treatment. Additionally, the beads exhibited successful sorption–desorption cycles, which demonstrated the beads’ reusability. The superior sorption capacity, selectivity, and reusability of ZIF-67@PES beads establish them as a promising material for uranium recovery, offering a sustainable approach to nuclear fuel resource management and environmental remediation.