Kinetic and equilibrium study of selenium removal from wastewater in mag-molecular process

Abstract

AbstractIn the present study, a mag-molecule was fabricated by functionalizing of silica-coated magnetite nanoparticles (MNPs) with 3-aminopropyl triethoxysilane (APTES). The amine functional group on surface of the particles was detected using Fourier transmission infrared spectroscopy technique. The morphology and dispersion of the functionalized magnetite nanoparticles (FMNPs) were observed through SEM images. The X-ray diffraction pattern illustrated the cubic crystal structure of MNPs with 28.79 nm of diameter which was almost identical with SEM images. The kinetic of adsorption was studied and pseudo-second-order represented the best fitting to the experimental data. In addition, chemical adsorption for MNPs and physical adsorption for FMNPs were diagnosed applying the Elovich model. The Freundlich model showed a better result for MNPs, which demonstrates a multilayer adsorption on heterogeneous surface, while the Langmuir model was well fitted to FMNPs data, which indicates a homogeneous adsorption...