Cellulose confined ferrihydrite nanocomposite beads for efficient As (III) removal

The concept of nanoconfinement holds immense promise in greatly enhancing the adsorption capacities of adsorbents. However, the translation of this potential into practical adsorbents has posed significant challenges. This study aims to explore a straightforward method for creating adsorbents with a nanoconfinement effect. Ferrihydrite nanoparticles were synthesized within a cellulose hydrogel matrix, resulting in ferrihydrite-loaded cellulose beads (FCB). Subsequently, a structural transformation of FCB was achieved through a dehydrationrehydration process, leading to a substantial size reduction and inducing irreversible alterations within the internal pore structure. This intricate metamorphosis culminates in the formation of cellulose-confined ferrihydrite (CCF) beads. The resulting CCF beads exhibit a striking increase in As(III) adsorption capacity, achieving an impressive 169.25 mg/g in comparison to the 117.26 mg/g exhibited by FCB. Rigorous column experiments confirm the real-world efficacy of CCF beads in removing As(III) from water, with a bed volume over 4000. Remarkably, the CCF beads demonstrate both good reusability and compliance with landfill disposal, as evidenced by toxicity characteristic leaching procedure testing. This study marks a significant breakthrough in adsorbent technology, offering a pragmatic route to crafting adsorbents with the coveted nanoconfinement effect.