Green synthesis of citric acid-crosslinked β-cyclodextrin for highly efficient removal of uranium(VI) from aqueous solution

In this paper, a green synthesized citric acid-crosslinked β-cyclodextrin polymer (CA-β-CD) was applied in removing uranium from aqueous solutions. Citric acid acts not only as cross-linker but also as functional groups for providing adsorption sites. The adsorption properties by varying experimental conditions were carried out by batch tests. The maximum adsorption capacity could reach 150 mg g−1. Adsorption process was fitted better with the pseudo-second-order and Freundlich model. Thermodynamic studies proved that adsorption process was spontaneous and endothermic. More significantly, the polymer showed high selectivity for uranium and excellent reusability, demonstrating that CA-β-CD can be utilized as a promising adsorbent for uranium.