Alginate beads impregnated with magnetic Chitosan@Zeolite nanocomposite for cationic methylene blue dye removal from aqueous solution.

ABSTRACT

In this study, magnetic bionanocomposite of sodium alginate (an anionic polysaccharide), chitosan (a cationic polysaccharide), impregnated with natural zeolite, and cross-linked with glutaraldehyde and CaCl2 in order to improve the stability, are prepared and used to methylene blue removal from aqueous solution. The synthesized magnetic Zeolite/Chitosan/Alginate (MZ/CS/AL) bionanocomposite was analyzed and characterized by FeSEM, EDX, XRD, BET surface area analysis, VSM, TGA, and FTIR techniques. The efficiency of the MZ/CS/AL biosorbent was studied by measuring the uptake using the batch and continuous technique experiments. The effect of contact time, pH, initial concentration of dye, and amount of adsorbent on dye adsorption capacity, kinetics, isotherm, thermodynamics, regeneration, and swelling were investigated. The results showed that the adsorption of methylene blue follows the pseudo-second-order kinetic model and Freundlich isotherm model. The thermodynamic results showed that dye adsorption process with synthetic adsorbent is an exothermic spontaneous process.