KINETICS, ISOTHERMS AND THERMODYNAMICS STUDY OF EOSIN YELLOW DYE ADSORPTION FROM AQUEOUS SOLUTIONS BY MnO2@rGO NANOCOMPOSITE

This study explores the use of MnO2@rGO nanocomposite as an adsorbent for Eosin Y dye. It was found that equilibrium for Eosin Y adsorption on the MnO2@rGO nanocomposite surface is achieved in 120 min. The nanocomposite demonstrated a high dye adsorption rate due to its extensive surface area, which facilitates substantial dye uptake. To assess the adsorption kinetics of Eosin Y on the MnO2@rGO surface; the data suggested that the pseudo-second-order model fit the data better. The Langmuir, Freundlich, and Temkin equations are examples of linear forms of adsorption isotherms that were investigated in this study and the substantial correlation coefficient for the Freundlich isotherm model suggests that the adsorption of Eosin Y dye on the MnO2@rGO nanocomposite surface is multilayered. Furthermore, the effects of pH, ionic strength, and thermodynamic factors on maximum adsorption were examined. In addition, thermodynamic functions including entropy (triangle S), enthalpy (triangle H), and Gibbs free energy (triangle G) were evaluated and the adsorption is physical.