Heavy and toxic metal ion removal by a novel polymeric ion-exchanger: synthesis, characterization, kinetics and equilibrium studies

Abstract

BACKGROUND A novel synthetic terpolymer resin involving anthranilic acid/o-toluidine/formaldehyde (AOTF) was synthesized for the recovery of harmful and heavy metal ions. The resin was characterized by physico-chemical, elemental, FTIR, NMR and SEM analysis. Batch separation was used under the following conditions: different concentrations of various electrolytes; variation of pH and time intervals to determine the ion-exchange properties of the resin for specific metal ions viz. Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Pb2+. Kinetic and equilibrium studies were also carried out with the terpolymer resin to evaluate the effectiveness of metal ion removal. RESULTS The ion-exchange capacity for the resin was found to be 5.02 milli mol g−1 indicating that the resin is a more effective ion-exchanger than some phenolic and polystyrene ion-exchangers. The amount of Cu2+, Ni2+ and Fe3+ taken up by the resin was 3.12, 2.25 and 2.34 milli mol g−1 at 0.5 mol L−1, respectively, hence the order of metal ion uptake at high concentrations is Cu2+ > Fe3+ > Ni2+. But at lower concentration of 0.01 mol L−1, the uptake of Zn2+ was 2.54, Co2+ was 1.77 and Pb2+ was 0.99 milli mol g−1, respectively, and the order of metal ion uptake is Zn2+ > Co2+ > Pb2+. CONCLUSION The results revealed that the synthesized ion-exchanger could act as a good ion-exchanging agent for the removal of toxic and hazardous wastes from industrial effluents. The results are compared with those for some commercial resins and earlier reported resins which indicate that the resin has an excellent capability to remove specific metal ions from waste solutions. © 2014 Society of Chemical Industry