Élimination d’un colorant textile (vert de malachite forme oxalate) par un matériau (MAGADIITE-Na)

Abstract

This research work is part of the valorization of microporous materials for the treatment of water contaminated by industrial dyes, particularly malachite green in its oxalate form. The study focused on magadiite, a lamellar-structured phyllosilicate, modified through the intercalation of an organic molecule N-(1-naphthyl) éthane-1,2-diamine dihydrochloride in order to enhance its adsorption capacity. In order to achieve our objective of obtaining an optimal adsorption yield, a study of adsorption isotherms and kinetics was carried out. The analysis of the isotherms revealed that the adsorption process can be modeled using the Langmuir, Freundlich, and Dubinin–Radushkevich isotherms. The optimal parameters studied include: the mass of the adsorbent, agitation time, solution concentration, and pH. Adsorption kinetics were analyzed using the pseudo-first-order and pseudo-second-order models. The study of adsorption isotherms showed a clear improvement in the maximum adsorption capacity following intercalation: the Langmuir model yielded a value of 323 mg/g compared to 4.40 mg/g before modification, and the Freundlich model revealed a significant increase in the KF coefficient. The results confirm the effectiveness of organic intercalation in optimizing the adsorptive properties of magadiite, both in terms of efficiency and selectivity. The modified material thus represents a promising and sustainable alternative for the removal of dyes from industrial effluents.