Synthesis and characterization of polyacrylamide zirconium (IV) iodate ion-exchanger: Its application for selective removal of lead (II) from wastewater

Polyacrylamide zirconium (IV) iodate was synthesized using the sol-gel technique. The synthesis conditions such as reactant concentrations and temperature were changed to optimize the ion exchange properties of the hybrid organic-inorganic ion exchange material. Zirconium oxychloride (0.1 M) was added to 0.1 M potassium iodate in the presence of 0.4 M acrylamide and heated at 70 °C for 6 h to yield the polyacrylamide zirconium (IV) iodate with maximum capacity. The ion exchange capacity was found to be 3.27 meq/g for Pb(II). The hybrid material has been characterized on the basis of chemical composition FTIR, XRD, TGA-DTA, SEM and EDX studies. Sorption studies showed that the hybrid cation exchanger has a high selectivity to Pb(II) in comparison to other metal ions. Its selectivity was evaluated by performing some important binary separations like Hg(II)-Pb(II), Cu(II)-Pb(II), Ni(II)-Pb(II), Fe(III)-Pb(II) and Cd(II)-Pb(II). In addition, the selective separation of Pb(II) was also achieved from a synthetic mixture containing a large number of metal ions with a recovery of ∼98.5%. The proposed method was successfully applied for the selective removal of Pb(II) from wastewater samples.