Arsenic adsorption behavior of aminated hydrous stannic oxide-polyacrylonitrile composite beads

The aminated hydrous stannic oxide-polyacrylonitrile (Am-HSO-PAN) composite beads were developed for the efficient removal of arsenic species from contaminated water. These beads exhibited high adsorption capacities for both As(III) and As(V), with the amination of PAN significantly enhancing the adsorption of As(V). Adsorption experiments revealed that the beads maintained high efficiency within pH_eq ranges of 2–9 for As(III) and 5–7 for As(V) and even in the presence of competing anions. The adsorption isotherms and kinetics indicated that As(III) and As(V) adsorption occurred through different mechanisms, with the beads showing maximum monolayer adsorption capacities of 33.0 mg/g for As(III) and 92.6 mg/g for As(V). Thermodynamic analysis revealed that the adsorption process is endothermic and spontaneous. The beads also showed stable performance over multiple regeneration cycles, demonstrating their potential as a cost-effective and efficient adsorbent for arsenic removal.