A chelating resin containing S, N and O atoms: Synthesis and adsorption properties for Hg(II)

Abstract

A novel chelating resin containing S, N and O atoms (PSME–EDA) was synthesized by using poly(2-hydroxyethylmercaptomethylstyrene) (PSME) and diethanolamine (EDA) as materials. Its structure was characterized by elemental analysis, Fourier transform-infrared spectra (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The adsorption of the resin for Hg 2+ was investigated. The saturated adsorption capacity of PSME–EDA for Hg 2+ could reach to about 1.1 mmol/g at 25 °C when the initial Hg 2+ concentration was 0.02 mol/l. Some factors affecting the adsorption such as temperature, reaction time and ion concentration were also studied. The results showed that adsorption was controlled by liquid film diffusion. The increasing of temperature was beneficial to adsorption. The Langmuir model was better than the Freundlich model to describe the isothermal process. The values of Δ G, Δ H, and Δ S calculated at 25 °C were −7.99 kJ mol −1, 22.5 kJ mol −1 and 34.4 J mol −1 K −1, respectively. The adsorption mechanism of PSME–EDA resin for Hg(II) was confirmed by X-ray photoelectron spectroscopy (XPS).