Efficient carbon interlayed magnetic chitosan adsorbent for anionic dye removal: Synthesis, characterization and adsorption study

The present paper describes the synthesis of a novel magnetic chitosan (CCF), in which the carbon-Fe₃O₄ core-shell nanoparticles play the role of magnetic part. The structure, property and morphology of the magnetic CCF were characterized by FT-IR, XRD, EDAX, SEM and BET techniques. Its adsorption performance was investigated for the removal of methyl orange from aqueous solutions by varying experimental conditions. The results showed the fast adsorption of methyl orange in wide pH range of 3–11 and the maximum adsorption capacity was found to be 425 mg g⁻¹ at 45 °C. The results of adsorption kinetics indicated that the adsorption mechanism was better described by the pseudo-second-order equation, whereas pore diffusion is the rate-controlling of adsorption kinetics. Furthermore, among different isotherm models, Langmuir and Sips isotherm models fitted well the equilibrium experimental data at different temperatures revealing the surface heterogeneity of the adsorbents. The adsorbent exhibited high adsorption performance, compared to the some other chitosan adsorbents reported in literatures.