Preparation of cross-linked magnetic chitosan-phenylthiourea resin for adsorption of Hg(II), Cd(II) and Zn(II) ions from aqueous solutions

► Chitosan was chemically modified through the reaction with phenylisothiocyanate. ► The modified chitosan-phenylthiourea cross-linked with formaldehyde in presence of magnetite to produce modified magnetic resin. ► The resulted resin characterized by various instrumental methods. ► The resin was applied to remove Hg2+, Cd2+ and Zn2+ from aqueous solutions.