Equilibrium and kinetics study of methyl violet adsorption by pineapple leaf fibers-cl-poly(acrylic acid-co-2-dimethyl amino ethyl acrylate) hydrogel

The pine apple leaf fiber-cl-poly(acrylic acid-co-2-dimethyl amino ethyl acrylate) hydrogel is prepared by crosslinked graft copolymerization of acrylic acid and 2-(dimethyl amino) ethyl acrylate onto the pine apple leaf fibers to be used as an adsorbent for the remove dye from aqueous solutions. Several characterization techniques like Fourier transform infrared spectroscopy field emission scanning electron microscopy-Energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. The synthesized hydrogel shows strong water swelling characteristics (780.93%) and also exhibits faster deswelling property. The methyl violet (MV) adsorption data are fitted well with the Freundlich isotherm model with maximum monolayer adsorption capacities 625 mg/g for MV. The equilibrium kinetics follow pseudo second order model together with intra particle diffusion, one step process. Thermodynamic parameters show that the MV adsorption by the hydrogel is spontaneous and endothermic in nature. The overall removal efficiency is found to be 98.23% under optimum condition.