Efficient As(III) Removal by Novel MoS(2)-Impregnated Fe-Oxide–Biochar Composites: Characterization and Mechanisms

[Image: see text] Sorbents that efficiently eliminate toxic metal(loid)s from industrial wastes are required for the protection of the environment and human health. Therefore, we demonstrated efficient As(III) removal by novel, eco-friendly, hydrothermally prepared MoS(2)-impregnated FeO(x)@BC800 (MSF@BC800). The properties and adsorption mechanism of the material were investigated by X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The synergistic effects of FeO(x) and MoS(2) on MSF@BC800 considerably enhanced As(III)-removal efficiency to ≥99.73% and facilitated superior As(III) affinity in aqueous solutions (K(d) ≥ 10(5) mL g(–1)) compared to those of FeO(x)@BC800 and MS@BC800, which showed 37.07 and 17.86% As(III)-removal efficiencies and K(d) = 589 and 217 mL g(–1), respectively, for an initial As(III) concentration of ∼10 mg L(–1). The maximum Langmuir As(III) sorption capacity of MSF@BC800 was 28.4 mg g(–1). Oxidation of As(III) to As(V) occurred on the MSF@BC800 composite surfaces. Adsorption results agreed with those obtained from the Freundlich and pseudo-second-order models, suggesting multilayer coverage and chemisorption, respectively. Additionally, MSF@BC800 characteristics were examined under different reaction conditions, with temperature, pH, ionic strength, and humic acid concentration being varied. The results indicated that MSF@BC800 has considerable potential as an eco-friendly environmental remediation and As(III)-decontamination material.