Preparation of a gallium-imprinted resin-capacitive deionization electrode and study of its gallium adsorption performance

Abstract

Aiming to overcome the shortcomings of slow adsorption rate and poor selectivity for gallium adsorption, this study successfully developed a novel gallium-imprinted resin composite electrode material. This material was prepared by using gallium-imprinted resin as an adsorbent and activated carbon as a conductive agent through a binder. Using capacitive deionization technology, the composite electrode material can effectively adsorb gallium from a strongly basic sodium aluminate solution. The material's innovative design not only provides a larger specific surface area and optimal pore size distribution but also demonstrates coordinated adsorption with gallium ions through functional groups such as hydroxyl, carboxyl, and amino groups. The experimental results confirm that the material achieves an adsorption capacity of 11.22 mg g⁻¹ at 1 V within 90 minutes, fitting the pseudo-second-order kinetic model and the Langmuir adsorption isotherm model, with a saturated adsorption capacity of 22.56 mg g⁻¹. Moreover, the material exhibits excellent cycle stability and reusability, retaining 88.9% of its original adsorption capacity after five adsorption–desorption cycles. These findings highlight the potential of this composite electrode material for efficient and sustainable gallium recovery.