Performance of cross-linked chitosan-zeolite composite adsorbent for removal of Pb2+ ions from aqueous solutions: Experimental and Monte Carlo simulations studies

Abstract

In this study, we investigated the performance of a cross-linked chitosan (Ch)-zeolite (Z) composite (Ch-Z) adsorbent for the removal of Pb2+ ions from water. The results revealed that the Ch-Z composite exhibited excellent adsorption performance for Pb2+ ions. The maximum adsorption capacity was found to be 275 mg g−1 at pH 4.5, Ch-Z composite dose of 5 g/L and an initial Pb2+ concentration of 1000 mg/L for 24 h. The adsorption equilibrium data and its kinetics followed a Langmuir and PSO models. Furthermore, thermodynamic parameters were determined, indicating that adsorption was spontaneous and endothermic. MC simulations were used to investigate the interaction between Pb2+ ions and the modeled composite. The considerable negative adsorption energy values confirm the strong affinity between the adsorbate molecules and the adsorbent surface. Overall, the Ch-Z composite adsorbent exhibited remarkable potential to remove Pb2+ ions from wastewater.