Magnetic Fe3O4-grafted cellulose/graphene oxide nanocomposite for methylene blue removal from aqueous solutions: Synthesis and characterization

Abstract

This research focuses on the development of efficient and cost-effective methods for the treatment of industrial wastewater. Magnetic Fe3O4 cellulose/graphene oxide nanocomposite was synthesized through free radical graft copolymerization of acrylic acid (AA) and acrylamide (AM) on the cellulose chains. The grafting copolymerization parameters, including molar ratio, temperature, and reaction time, were optimized. Structural characteristics of the prepared samples were analyzed using FT-IR, XRD, and VSM techniques, while morphological characteristics were examined using FE-SEM and HR-TEM. The prepared samples were evaluated for their adsorption capacity towards methylene blue (MB) dye under various conditions. The factors controlling the adsorption process, such as pH, contact time, adsorbent dose, and initial MB concentration, were studied. The experimental data were successfully described by the pseudo-second-order model, and the equilibrium adsorption results fitted the Freundlich and Dubinin-Radushkevich isotherms. Thermodynamic studies revealed that the adsorption process was endothermic and occurred spontaneously, leading to greater disorder. Optimal conditions for MB adsorption onto the magnetic cellulose/graphene oxide nanocomposite were determined to be pH 7, a contact time of 7 h, and an adsorbent dose of 0.0375 g in a 30 mg/L dye solution. The inclusion of magnetite and graphene oxide into cellulose resulted in enhanced removal efficiency of the dye, with the magnetic cellulose/graphene oxide nanocomposite exhibiting a removal percentage of 97%. These findings demonstrate the potential of the magnetic cellulose/graphene oxide nanocomposite as a powerful adsorbent for the removal of methylene blue dye from aqueous solutions, offering promising prospects for the treatment of industrial wastewater.