The crosslinked poly[3-(methacryloylamino)propyl] dim ethyl(3-sulfopropyl)ammonium hydroxide], P(MAPDSA), and poly[3-(methacryloylamino)propyl]dimethyl(3-sulfopropyl)ammonium hydroxide-co-acrylic acid], P(MAPDSA-co-AA), were synthesized by radical polymerization. The resins were completely insoluble in water. Due to the lower metal ion retention of P(MAPDSA), the metal ions investigated under competitive and noncompetitive conditions for Cu(II), Cd(II), Hg(II), Zn(II), Pb(II), and Cr(III) ions by batch and column equilibrium procedures were carried out only for P(MAPDA-co-AA), particularly for Hg(II). The resin-Hg(II) ion equilibrium was achieved before 15 min. The resin showed a maximum retention capacity value for Hg(II) at pH 2 of 1.89 meq/g. The resin showed a high selectivity to Hg(IT) ions. The recovery of the resin was investigated at 25 degrees C with different concentrations of HNO3 and HClO4. (c) 2005 Wiley Periodicals, Inc.