Radiation synthesis of Fe3O4/SiO2/glycidyl methacrylate/acrylonitrile nanocomposite for adsorption of basic violet 7 dye: Kinetic, isotherm, and thermodynamic study

Abstract

New functional nanocomposites (Fe3O4/SiO2/GMA/AN) were synthesized by γ‐irradiation copolymerization of glycidyl methacrylate (GMA) and acrylonitrile (AN) of different ratios onto the surface of Fe3O4/SiO2 nanoparticles. The chemical structure and morphology of the nanocomposites were characterized by Fourier transform infrared (FTIR), X‐ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The influences of GMA/AN composition ratios (75/25, 50/50, and 25/75 v/v) of nanocomposites on the adsorption of basic violet 7 dye from aqueous solutions was investigated. The Fe3O4/SiO2/GMA/AN nanocomposite with GMA/AN compositions ratio of (25/75 v/v) provides maximum adsorption capacity, and thus it was selected as the suitable ratio for modification by amidoximation reaction. The influences of contact time, pH, temperature, initial concentration, and adsorbent dosage on the adsorption of dye onto Fe3O4/SiO2/GMA/AN‐amidoxime were evaluated. The adsorption capacity of poly (GMA/AN), Fe3O4/SiO2/GMA/AN, and Fe3O4/SiO2/GMA/AN‐amidoxime was 18.7, 114.1, and 181.3 mg/g, respectively. The optimum removal efficiency (90.65%) of dye by Fe3O4/SiO2/GMA/AN‐amidoxime was obtained after 120 min contact time, 200 mg/L dye concentration, and pH 7. The adsorption of dye onto the Fe3O4/SiO2/GMA/AN‐amidoxime follows pseudo‐second‐order adsorption kinetics and fits Langmuir adsorption isotherm, and the adsorption process is endothermic and spontaneous. The prepared Fe3O4/SiO2/GMA/AN‐amidoxime confirmed their possible use as a successful adsorbent for the adsorption of basic violet 7 from wastewater.