High-capacity biomass-based composite aerogel for efficient multi-ion adsorption of vanadium, molybdenum, and nickel

Abstract

Biomass adsorbents have great potential in the fields of wastewater treatment and metal recovery. However, single biomass materials have low adsorption capacities. A novel composite biomass aerogel (Co-Zn/DMIM@NCC) was designed and prepared for the adsorption of vanadium, molybdenum, and nickel ions by in situ growth of metal–organic framework (MOF) on cellulose. The growth of MOF provided sufficient ion transport channels for metal ions, making them easier to diffuse from the outside to the inner adsorption sites of the aerogel. Adsorption experiments showed that MOF improved the composite material’s adsorption performance. The maximum adsorption capacity for V(V) is 1035.67 mg/g, for Mo(VI) is 908.06 mg/g, and for Ni(II) is 400.35 mg/g. In a mixed ion solution, the removal rate exceeded 80% and remained above 75% after five cycles, indicating good stability. The prepared adsorbent exhibited excellent removal and selective adsorption capabilities for vanadium, molybdenum, and nickel ions. Adsorption studies revealed different adsorption regions on the adsorbent surface, indicating a complex adsorption process. Comprehensive characterization indicated that the adsorption involved chemical adsorption, electrostatic interactions, redox reactions, and chelation processes. This research offers a framework for the creation and synthesis of innovative adsorbents that integrate MOF and cellulose, serving as a valuable reference for future developments in the field.