LAUSR

Abstract To simultaneously remove various heavy metals from wastewater, a novel two-step approach, which involves grafting of monomers and subsequent derivation with mixed ligands, was proposed to develop dual-function chelating resin with high capacity. Specifically, glycidyl methacrylate (GMA) was grafted onto polystyrene resin via surface-initiated atom transfer radical polymerization and followed by derivation with 5-aminosalicylic acid (ASA) as hard base and 2-(4-imidazolyl)ethylamine (IMEA) as soft base to obtain the polymeric brush-type ASA/IMEA-PGMA@PS. The adsorption property was investigated by Cu(II) and Pb(II), Cd(II) and Ag(I), as well as Fe(III) and Cr(III), which are junctional, soft and hard acids, respectively. The adsorption amounts depend largely on the ratio of two ligands. At 1:1 of ASA to IMEA, the adsorption capacities of the obtained resin are 0.87, 1.57, 0.70, 1.47, 1.90 and 1.19 mmol/g for Cu(II), Pb(II), Cd(II), Ag(I), Fe(III) and Cr(III), respectively. Moreover, the adsorbent displays strong salt tolerance and excellent reusability. Furthermore, the adsorption obeys Langmuir model and the pseudo second-order kinetics model, and is mechanically dominated by chelation interaction. These findings demonstrate that the prepared resin can be applied in the treatment of complicated saline effluent, and the proposed approach has potential to develop variety of dual-function chelating resins.