Modification and characterization of PET fibers for fast removal of Hg(II), Cu(II) and Co(II) metal ions from aqueous solutions

► PET fibers were graft copolymerized with acrylonitrile. ► Further modification was carried out through the reaction with hydrazine hydrate and then potassium thiocyanate. ► The resulted chelating fibers were characterized by various instrumental methods. ► The fibers were applied to remove Hg2+, Cu2+ and Co2+ from aqueous solutions.