Synthesis of novel magnesium ferrite Schiff base chitosan nanocomposite for efficient removal of pb(II) ions from aqueous media

In this study, a novel MgFe₂O₄-Schiff base-chitosan nanocomposite was synthesized using a straightforward crosslinking method. The synthesis involved integrating MgFe₂O₄ nanoparticles with modified chitosan through a Schiff base formed by the reaction between terephthalaldehyde and aminopyrazine. A comprehensive characterization was performed, including X-ray diffraction analysis, which verified the crystalline structure and the successful incorporation of MgFe₂O nanoparticles into the chitosan-Schiff base matrix. Scanning electron microscopy revealed a distinct surface morphology, characterized by a rough, non-uniform alignment resulting from the strong interactions between the nanoparticles and the Schiff base-chitosan matrix. Additionally, energy-dispersive X-ray analysis verified the elemental composition of the nanocomposite, revealing distinct peaks corresponding to carbon, nitrogen, oxygen, magnesium, and iron. The nanocomposite exhibited outstanding performance as a nanoadsorbent for the efficient removal of Pb(II) ions from aqueous media through electrostatic attraction and complexation mechanisms, achieving a maximum adsorption capacity of 290.7 mg g^-1. The adsorption process was determined to be spontaneous, endothermic, and chemically driven, aligning well with the Langmuir isotherm model and pseudo-second-order kinetics. The optimal conditions for maximum Pb(II) ions removal were determined to be a pH of 5.5, a contact time of 100 min, and a temperature of 328 K. Furthermore, the nanocomposite demonstrated excellent recyclability, retaining over 94.8% of its initial removal efficiency after five consecutive adsorption-desorption cycles. This study highlights the nanocomposite's potential as an eco-friendly, cost-effective, and highly efficient material for practical applications in water treatment, addressing the urgent need for sustainable solutions to heavy metal contamination.