Microwave-assisted fabrication for synthesis of magnetite chitosan-modified polymer composite hydrogel as rapid removal adsorbent for effective remediation of hazardous contaminants

The present work aimed to synthesize chitosan-g-poly-(CA-co-DMAEMA)/Fe 3 O 4 polymer composite hydrogels by microwave-assisted polymerization and its application for removing Chicago sky blue and crystal violet dyes present in solution. Prepared material was characterized by analyzing various spectroscopic methods. Swelling response of synthesized polymer composite hydrogels was investigated at different pH values: 2 and 12. The final concentration of dyes in solution and % removal capacities of adsorbent at various experimental condition were evaluated. The adsorption kinetics and equilibrium adsorption isotherms are in accordance with pseudo-second-order model and the Freundlich isotherm model, respectively. Adsorption experiments showed that synthesized material has high adsorption capacities (66.66 mg/g for Chicago sky blue and 161.81 mg/g for crystal violet) and faster rate within short time. Additionally, it exhibited excellent recyclability without significant efficiency loss for at least five cycles. Thus, chitosan-g-poly-(CA-co-DMAEMA)/Fe 3 O 4 polymer composite hydrogels exhibit great potential for used in efficient environmental and economical remediation. Lastly, it is proved that material is suitable for pollutant treatment which can be easily separated by external magnet. Graphical abstract Graphical representation of features of polymer composite hydrogel and their dye adsorption