Preparation of new bio-based chitosan/Fe₂O₃/NiFe₂O₄ as an efficient removal of methyl green from aqueous solution

Modified chitosan with various functional groups has high potential as an efficient adsorbent in removing water pollution. In this study, new magnetic adsorbent, bio-based chitosan/Fe₂O₃/NiFe₂O₄, was successfully prepared by green chemistry route involving mixing of chitosan as core moiety and Fe₂O₃/NiFe₂O₄ nanocomposite, and slow evaporation of solvent. Synthesized chitosan/Fe₂O₃/NiFe₂O₄ was characterized by FT-IR, TGA, XRD, VSM and FE-SEM. The FT-IR and XRD results confirmed that the successful preparation of chitosan/Fe₂O₃/NiFe₂O₄. Uniform dispersion of Fe₂O₃/NiFe₂O₄ nanoparticles with low aggregation was confirmed by FE-SEM. The as-prepared magnetic chitosan/Fe₂O₃/NiFe₂O₄ was developed as solid phase adsorbent to remove methyl green (MG) dye from aqueous solutions. Several important parameters such as contact time, pH, temperature and adsorbent dosage were investigated systematically. The high and fast MG dye removal (≈ 80%) occurs after 30 min. The optimal conditions for MG removal was recorded at pH = 8, contact time of 60 min, adsorbent dosage of 0.2 g and 25 °C and displayed a high MG dye removal percentage of 96.51% and adsorption capacity of 77.22 mg/g.