Investigation of methylene blue adsorption on activated carbon surfaces: A combined approach of experimental study and molecular simulation

Abstract

Wastewater containing methylene blue, commonly found in dyeing and textile effluents, poses significant environmental risks if left untreated. It can severely pollute water bodies, disrupt ecosystems, and threaten human health due to its toxicity. This study examined the ability of activated carbon to adsorb methylene blue from water. The activated carbon was pre-treated with various KOH ratios, achieving a maximum adsorption capacity of 619.92 mg/g. The adsorption process was analyzed using kinetic and isothermal models. Results showed that the process was best described by the pseudo-second-order kinetic model and the Langmuir isotherm model, both demonstrating high R² values. Molecular simulation methods were applied to explore the adsorption mechanism in greater detail. The findings indicated a multilayer adsorption mechanism dominated by electrostatic interactions, which facilitate strong bonding between the activated carbon surface and methylene blue molecules. Overall, the study highlights the potential of activated carbon as an effective solution for removing methylene blue from polluted water sources.