Green synthesis of magnetic nanocomposite by Cordia Africana (CA) leave extract for the treatment of Methylene blue contaminated water

The magnetic behavior of individual magnetite (Fe3O4) nanoparticles (MNPs) has arisen considerable attention in environmental application. However, magnetic properties and stability weaken due to their high susceptibility to chemical activity (oxidation). Efforts have increasingly been made to encapsulate MNPs by green organic matrix, which considerably improve functionality, stability, cost and reduce back toxicity. Besides, the use of natural zeolite materials has been reported to endows considerable dispersibility and chemical stability for the composite MNPs. In this study, bio-based magnetite nanoparticles were synthesized using an aqueous extract of Cordia Africana (CA) leaves incorporated into the modified Natrolite (NAT) framework as an adsorbent for methylene blue (MB)dye removal from aqua solution. The prepared high dispersible Magnetite-NAT Nanocomposite (M/NAT-NC) was characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), and scanning electron microscope (SEM). The optimum adsorption efficiency of M/NAT-NCs was estimated by employing Response Surface Methodology (RSM)-based Box-Behnken Design (BBD) at different parameters. Accordingly, 0.5 g M/NAT-NCs, 40 mg/L, and pH 9 at 40 min were found to be the optimal conditions for best removal (98.6%). The adsorption data fitted best with the pseudo-second-order and Freundlich model, and the negative value of ∆G0 confirms the feasibility and spontaneity of the MB adsorption onto M/NAT-NCs. Besides, the regeneration of exhausted M/NAT-NCs reflected nearly similar removal efficiency as the new one; as such, M/NAT-NCs could be reasonably used for cationic dyes removal from aqueous media