SYNTHESIS CHARACTERISATION AND EVALUATION OF HYDROGELS FOR AHELATION OF METAL IONS

Abstract

Superabsorbent anionic polyelectrolytic hydrogels have been prepared by redox polymerization of acrylic acid in the presence of polyethylene glycol diacrylate as the cross linker. Although the linear analog of polyacrylate has been reported to form metal complexes with divalent metal ions, its use for removal of heavy metals from aqueous solutions for practical purposes is restricted, because of its inherent water solubility. To address this issue, crosslinking of this polymer has been attempted to synthesize hydrogel, which has an advantage of being stable in aqueous medium over a wide range of pH. The synthesized hydrogel was characterised by swelling studies, FTIR, elemental analysis and thermal analysis. This chelating hydrogel bearing O, O donor groups was found to exhibit high hydrogel capacity of 41.1, 58.2, 43.1 and 81.2 mg/g for metal ions such as Cr6+, Ni2+, Cu2+ and Pb2+ respectively under optimum conditions. Various physicochemical parameters like pH, concentration and inte...