Synthesis and characterization of graft copolymers of N-Vinyl-2-Pyrrolidone onto guar gum for sorption of Fe2+ and Cr6+ ions

To develop low cost and environment friendly technologies for removal of metal ions from water systems, graft copolymers based on guar gum and poly(N-Vinyl-2-Pyrrolidone) were synthesized. The optimum reaction conditions were evaluated for grafting by varying nature and amount of solvent, change in concentration of monomer and initiator, reaction time and temperature. Graft copolymers were characterized by FTIR, SEM, XRD, thermal analysis and swelling studies. Sorption of Fe2+ and Cr6+ ions on graft copolymers was investigated as a function of percent grafting, change in metal ion concentration and temperature to define their end-uses in separation technologies.