Sustainable self-assembled gum tragacanth hydrogel for eco-efficient uranium recovery from contaminated water

Abstract

Improper treatment of uranium wastewater from rare earth tailings can have detrimental effects on ecosystems and human health. Therefore, it is crucial to develop effective methods for uranium removal to ensure safe discharge. Herein, we present a novel hydrogel composite (GTA–2D MMT) synthesized through self-assembly, integrating gum tragacanth (GT) functionalized with amidoxime groups and exfoliated two-dimensional montmorillonite (2D MMT). This hydrogel capitalizes on the high cation exchange capacity and abundant functional groups of 2D MMT to enhance mechanical strength while mitigating the excessive volume expansion commonly observed in polysaccharide-based hydrogels. The aluminum hydroxyl and oxygen atoms at the edges of 2D MMT interact with the amino group of the GT, restricting polymer chain mobility and improving structural stability. With an adsorption capacity of up to 441.32 mg g⁻¹, GTA–2D MMT exhibits an excellent uranium removal efficiency of 94.6% in tailings wastewater while maintaining its structural integrity through multiple regeneration cycles. These results highlight the potential of GTA–2D MMT as a robust and eco-friendly adsorbent for uranium remediation, advancing the design of high-performance materials for wastewater treatment.