LAUSR

In the present work, a poly-Schiff base with a capability to remove the dye pollutant from aqueous solutions was synthesized. For this purpose, firstly poly(glycidyl-alt-maleic anhydride) (PGMA-MAn) copolymer was prepared by free-radical polymerization. Then, the PGMA-MAn was modified with melamine. Finally, the melamine-modified PGMA-MAn copolymer was further reacted with 3-pyridinecarboxaldehyde to form the poly-Schiff base. The synthesized poly-Schiff base was employed to study the dye pollutants adsorbing from aqueous solutions, and Congo red dye was selected as a typical dye. Different adsorption parameters were investigated and optimized, such as pH, adsorbent amount, initial concentration of the dye and contact time. By adjusting these parameters, the adsorption percentage reached the value of 98%. Moreover, the adsorption isotherms were studied and fitted with the Langmuir, Freundlich and Dubinin–Radushkevich models. Besides, the kinetic studies were carried out using the Lagergren pseudo-first-order and the Ho pseudo-second-order equations.