Chitosan-gelatin/cetyltrimethylammonium bromide magnetic polymer composites as reusable high performance adsorbent for AR 18 removal

Magnetic chitosan (CS) cross-linked gelatin (Gel) polymer composites (MCGC) were fabricated by reacting CS with Gel in the present of carboxyl modified Fe3O4 nanoparticles and cetyltrimethylammonium bromide using glutaraldehyde as a crosslinking agent. MCGC possessed high zeta potential, abundant active functional groups including amino and hydroxyl groups and facile magnetic separation properties. The prepared MCGC exhibited excellent adsorption performance for AR 18 and the adsorption capacity reached as high as 344.63 mg/g. The adsorption kinetics was fitted well with the pseudo-second order model, while the adsorption isotherms followed the Redlich-Peterson equation best. The thermodynamic studies indicated the adsorption process was exothermic and spontaneous. The adsorption mechanism was studied including electrostatic interaction, hydrogen-bond interaction and π-π stacking between dyes and MCGC. Desorption and renewable experiments proved MCGC possessed high regeneration properties and reusability as an adsorbent.