Synthesis of poly(amidoamine) dendrimer-based dithiocarbamate magnetic composite for the adsorption of Co2+ from aqueous solution

Abstract

Poly(amidoamine) dendrimer-based dithiocarbamate magnetic composites (Fe3O4@SiO2–PAMAM–DTC) were synthesized for the adsorption of Co2+ from aqueous solution. The adsorbents were characterized by X-ray diffraction (XRD), fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TG), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrometry (EDS), vibrating sample magnetometer (VSM) and N2 adsorption/desorption. The effects of different factors (such as solution pH, adsorption time, adsorption temperature, adsorbent dosage and competitive ions etc.) on adsorption were investigated. The experimental results showed that, the kinetic data was fitted to the pseudo-second-order model, and the adsorption data was consistent with the Frenudlich isotherm model. The adsorption process was spontaneous and endothermic. The magnetic composite is easy to synthetise, and the most important thing is that it can be quickly separated from aqueous solution by a magnet. The Fe3O4@SiO2–PAMAM–DTC composite can be a potential adsorbent for the removal of Co2+ from aqueous solution.