Selective capture of anionic and cationic dyes via chitosan-g-poly-(IA-co-DADMAC)/Fe3O4 polymer composite hydrogel

In this work, we designed novel chitosan-g-poly-(IA-co-DADMAC)/Fe3O4 polymer composite hydrogel using in situ ultrasonic wave-assisted polymerization method and applied for the uptake of methylene blue (MB) and congo red (CR) dyes from aqueous solution. The polymer composite hydrogel was characterized via FT-IR, XRD, TGA, FE-SEM, BET and VSM analysis. More interestingly, dyes can be efficiently adsorbed and after adsorption conveniently separated from solution by using external magnet. For dye adsorption studies, congo red (anionic dye) and methylene blue dyes (cationic dye) were taken as the target pollutant. Adsorption isotherm followed Fruendlich model with 862.06 mg/g and 1111.11 mg/g, respectively, adsorption capacity and the adsorption kinetics was most appropriately explained using pseudo-second-order kinetic model. This study will provide a new perspective for the design and fabrication of novel, safe and effective systems for dye removal.

Automated summary

In this study, a novel chitosan-g-poly-(IA-co-DADMAC)/Fe3O4 polymer composite hydrogel was designed and synthesized using in situ ultrasonic wave-assisted polymerization method for the adsorption of methylene blue and congo red dyes from aqueous solution. The composite hydrogel showed high adsorption capacity and adsorption rate, and the adsorbed dyes could be conveniently separated from the solution using an external magnet. The findings of this study provide a new perspective for the design and fabrication of novel, safe, and effective systems for dye removal.