Chelating resins for mercury extraction based on grafting of polyacrylamide chains onto styrene-divinylbenzene copolymers by gamma irradiation

Chelating resins for mercury adsorption were prepared by grafting polyacrylamide chains onto styrene-divinylbenzene (Sty-DVB) copolymers by applying gamma radiation. Sty-DVB copolymers were synthesized by aqueous suspension polymerization employing different synthesis conditions. The copolymers were characterized by apparent density, surface area, pore size distribution and swelling capacity. The copolymers were irradiated using a 60Co-γ source at room temperature in the presence of acrylamide solution in methanol. The grafting reaction was evaluated with the aid of elemental analysis, FTIR and thermogravimetric analysis (TGA). Hg(II) uptake measurements were carried out in batch experiments. The results showed that these resins can be successfully used for Hg(II) adsorption at ppm levels. The porosity degree of the copolymers influences the grafting yield as well as the Hg(II) complexation capacity of the chelating resins.