Zeid Abdullah Al-Othman¹, Mohamed Abdelaty Habila^1,*, Rahmat Ali¹ and Mohamed Salah El-Din Hassouna²

¹Advanced Materials Research Chair to Affliction, Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia

²Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, 163 El-Horreya Avenue, P.O. Box 832, Alexandria, Egypt

*Corresponding author: Tel: +966 595184785; E-mail: mhabila@ksu.edu.sa

This study aimed to evaluate and optimize the removal of methylene blue onto low cost starting material activated carbon. The effects of pH, contact time, initial concentration on adsorption process were investigated. Results showed that effective adsorption was occurred in the pH range of 5-12. The maximum adsorption capacity (140.03 mg/g) was obtained at contact time 480 min, at initial methylene blue concentration of 150 ppm. Adsorption kinetics of methylene blue was analyzed by pseudo first order, pseudo second order and intraparticle diffusion models. Results showed that methylene blue adsorption onto activated carbon followed second order kinetics models most appropriately. Thermodynamic parameters; DGº, DHº and DSº indicate that the sorption process was spontaneous and endothermic in nature. The magnitude of DGº was -6.27 to -12 kJ/mol, the standard enthalpy and the entropy values in the range of 25-50 ºC were obtained as 44.13 kJ mol^-1 and 158.3 kJ mol^-1 K^-1.

Copyrolysis, Municipal solid waste, Chemical activation, Activated carbon, Adsorption, Kinetic models.