Facile hydrothermal fabrication of functionalized multi‐layer graphene oxide encapsulated chitosan beads for enriched fluoride adsorption

Abstract

AbstractThe present exploration was focused on the fabrication of environmental friendly adsorbent materials using graphene oxide (GO) and chitosan (CS). To modify GO by functionalization with sulphonic acid gives sulfonated GO (SGO), which possess high defluoridation capacity (DC) than GO. To boost the DC, easily separation and make it in an exploitable form of SGO material, SGO was incorporated onto biopolymer CS gives SGO/CS hybrid composite beads and employed for efficient defluoridation of water. The various influencing parameters of adsorption system viz., shaking time, adsorbate pH, initial fluoride concentration, adsorbent dosage, temperature, and interfering anions were optimized to obtain the highest DC. The DC of SGO/CS composite beads were found to be 4950 mg.kg−1 within 30 min for 10 mg/L of preliminary adsorbate solution by 0.1 g dosage. The surface and structural characterization/properties of the prepared SGO/CS composite beads were evaluated by FTIR, TGA, SEM, and XPS investigations. The attained equilibrium data were predicted by isotherms like Fruendlich, Dubinin‐Radushkevich (D‐R), and Langmuir. The acquired equilibrium data of thermodynamic investigations facilitate to predict the nature of fluoride adsorption process onto SGO/CS composite beads. The plausible defluoridation mechanism of SGO/CS composite beads was discussed in detail. The applicability of SGO/CS beads was investigated at field environment with field water sample.