Equilibrium and Kinetic Modeling of the Adsorption of Naphthalene and Benzene onto Calcined Modified Clay

This research examines the adsorption behavior of naphthalene and benzene onto thermally modified clay using equilibrium and kinetic modeling techniques. Kinetic approaches encompassing Pseudo-First Order, Pseudo-Second Order, Elovich, Intra-Particle Diffusion, and Power Function models were applied to both unmodified and modified clay. Among these, the Elovich model exhibited the highest correlation coefficient (R²), indicating its superior ability to describe the adsorption process. For benzene adsorption, the Elovich model yielded an R² value of 0.9844 for unmodified clay and 0.9666 for modified clay, while for naphthalene adsorption, the Elovich model provided an R² of 0.9770 for unmodified clay and 0.9547 for modified clay. The equilibrium adsorption characteristics of both pollutants were evaluated, revealing that benzene achieved equilibrium in 26 hours, with concentration reductions from 5.2 mg/L on untreated clay to 2 mg/L on modified clay. Naphthalene reached equilibrium within 22 hours, experiencing significant concentration drops. The findings underscore the enhanced adsorption efficiency of calcined modified clay compared to its unmodified counterpart, positioning it as a viable material for wastewater treatment, pollution mitigation, and separation of organic contaminants.