Tertiary Nanocomposites of Metakaolinite/Fe3O4/SBA-15 Nanocomposite for the Heavy Metal Adsorption: Isotherm and Kinetic Study

Abstract

Magnetite nanoparticles (Fe3O4) and their kaolinite and SBA-15 (MFSBA-15) composites were fabricated and evaluated their adsorption capability of heavy-metal ions Pb(II) and Co(III) from aqueous solution. The morphology, phase structure, and composition of nanocomposites are investigated for scanning electron microscope (SEM), X-ray diffraction (XRD), VSM, TGA, and Fourier-transform infrared (FT-IR) spectroscopy. With a particle size of 100–250 nm, the material surface was heterogeneous. This study highlighted several parameters affecting the metal ion adsorption, such as initial concentrations, adsorbent dose, pH, and contact time. At optimum pH 6, 8, and 10 for Pb(II), and Co(III) ions, balance and kinetic experiments were conducted at 29 °C. The model predictions were adequately following the experimental results, and the MFSBA-15 nanocomposites were successfully used to isolate heavy metals from aqueous solutions. The maximum adsorption efficiency for MFSBA-15 material for Pb(II) and Co(III) was 248.213 and 109.254 mg/g, respectively. For regenerative studies, the composite was used. The analysis indicated that it was possible to reuse the adsorption of heavy metals from aqueous solutions over seven cycles without any adsorption capacity modification.