Removal of Pb (II) and Cd (II) Ions by MnFe2O4@SiO2@VTMS Nanocomposites Hydrogel from Aqueous Solutions

Abstract In this work, magnetic nanocomposite hydrogel was produced via grafting copolymerization of acrylic acid (AA) and acrylamide (AAm) in the presence of MnFe2O4@SiO2@Vinyltrimethylsilane (VTMS) as a cross-linking agent. To effectively absorb Pb (II) and Cd (II) from an aqueous solution, the prepared magnetic nanocomposite hydrogel was applied. XRD, VSM, FT-IR, SEM, EDS, and TEM VSM, SEM, TEM, EDS, FT-IR, and XRD spectroscopic methods validated the structure of the prepared nanocomposite hydrogel. In addition, thermal characteristics were evaluated by TGA and DTG. The features that influence the absorption of heavy metal ions include pH solution, treatment time, starting concentration of ions, temperature, and sorbent quantity experimented. Employing Langmuir, Freundlich, and Temkin, the adsorption isotherm was investigated at various temperatures. The adsorption data best fitted The Langmuir isotherm model. The absorption kinetics models such as intraparticle, pseudo-first-order, pseudo-second-order in metal ion solutions of 25, 50, 100, and 150 mg/L-1 were studied. The absorption results were well explained by pseudo-first-order model. The maximal absorption capacities of magnetic nanocomposite hydrogel for Pb (II) and Cd (II) elimination from a 150 mg/L-1 metal solution were 131 and 126 mg/g, respectively. The absorbent was employed effectively for four cycles of adsorption and desorption. Therefore, the nanocomposite hydrogel examined in this work may be used for various water filtration purposes, notably for the elimination of toxic metals.