Selective adsorption and separation of gadolinium with three-dimensionally interconnected macroporous imprinted chitosan films

We successfully prepared three-dimensionally interconnected macroporous imprinted chitosan films (3DIM-IFs) by template-assisted assembly. Imprinted chitosan films exhibiting an interconnected macroporous structure are used as adsorbents for efficient and selective adsorption of gadolinium ions (Gd(III)). Saturation adsorption capacity of 3DIM-IFs for Gd(III) is up to 51.36 mg g⁻¹ at 298 K, which is significantly higher than adsorption capacities for most reported Gd(III) imprinted adsorbents during recent years. Because of highly selective imprinted sites, imprinted films possess significant selectivity of Gd(III) than other rare earth ions. Moreover, 3DIM-IFs can be easily and rapidly retrieved without the need of additional centrifugation or filtration, greatly facilitating the separation process. Reusability tests demonstrated that the materials can be repeatedly used without significant loss in adsorption capacity, enhancing their potential application for recovery of Gd(III).