Immobilization of ZIF-8 into biomass aerogel for uranium enrichment from radioactive wastewater

Advances in nuclear energy have led to steady accumulation of radioactive uranium wastewater, requiring the worldwide implementation of safe and efficient disposal methods. Adsorption has become a viable solution for purifying uranium-contaminated wastewater and recovering uranium resources due to its efficiency, environmental compatibility, and simplicity. This study utilized konjac glucomannan’s (KGM) gel properties to create a ZIF-8@KGM aerogel. Liquid nitrogen-induced rapid directional freezing combined with KGM’s exceptional plasticity yielded an aerogel with a uniform layered structure and directional channels. ZIF-8 (2-Methylimidazolezincsalt) particles are dispersed uniformly within the aerogel pores, significantly improving adsorption site accessibility. Compared with ZIF-8, the [email protected] aerogel achieved improved kinetics and adsorption capacity for uranium separation. After 90 min in a 200 mg/L acidic U(VI) solution, it achieved 96.4 % removal efficiency and a maximum capacity of 687.8 mg/g. Mechanistic studies revealed synergistic adsorption: KGM’s oxygen-containing functional groups coordinated with uranyl ions, together with the nitrogen-containing groups and hydroxyl Zn(Ⅱ) sites on ZIF-8 particles. Overall, this approach provides a promising strategy for uranium wastewater remediation that exhibits broader applicability in water treatment.