Microwave Assisted Synthesis of Polyacrylamide Grafted Guar Gum and its Application as Flocculent for Waste Water Treatment

Industrial and municipal waste frequently contain metal ion, of which, industrial waste constitutes the major source of pollution in natural water. An abstraction of these colloidal metal particles from wastewaters becomes a serious challenge for the industries. Attention has been increasingly paid to natural polymer flocculants owing to their wide availability, biodegradability, and environment-friendliness. In the present investigation, polyacrylamide grafted guar gum (GG-g-PAAm) was synthesized using microwave assisted method in the presence of ceric ammonium nitrate (CAN) as an initiator. The synthesis was optimized for highest percentage grafting by varying the microwave irradiation time, power, initiator, and monomer concentration. Characterization of the grafted product was performed by the FTIR and TGA methods. The copolymer resulting from the graft copolymerization reaction was subsequently treated with gluteraldehyde (GA) to obtain crosslinked hydrogel. Further, flocculation efficacy of crosslinked hydrogel was studied by standard ‘Jar test’ procedure in 0.25% kaolin suspension, to assess its application as flocculating agent for wastewater treatment.