Removal of methylene blue dye from aqueous solution using activated charcoal modified manganese ferrite (AC-MnFe2O4): kinetics, isotherms, and thermodynamics studies.

The potential of activated charcoal supported on Manganese ferrite (AC-MnFe2O4) powder, for the removal of methylene blue (MB) dye from aqueous solution was investigated. Batch adsorption studies were conducted and various parameters such as initial dye concentration, pH, and temperature were studied to observe their effects in the dye adsorption process. The optimum conditions for the adsorption of MB onto AC-MnFe2O4 were found to be time and pH dependent. The amount of dye adsorbed increases from 1.67 to 27.49 mg/g as the initial concentration increases from 10 to 50 mg/L. Kinetics modeling showed that the pseudo-second-order model best described the process while Freundlich isotherm gives the best fit. The maximum adsorption isotherm of 77.44 mg/g was obtained for the adsorbent. The adsorption/desorption study showed that the adsorbent has over 99% for more than seven cycles. Increase in temperature from 30 to 50 °C raised the Qe, equilibrium adsorption capacity from 86.39 to 101.79 mg/g while the thermodynamic study shows that the process is favored with ΔG < 0, ΔH value shows that the process is endothermic. [ABSTRACT FROM AUTHOR]