Removal of Mn (II) from Aqueous Solutions by Activated Carbons Prepared from Coula edulis Nut Shell

摘要

The batch removal of Mn (II) from aqueous solution using activated carbon prepared from Coula edulis nut shell was performed. Different experimental conditions such as: pH (2-6), Mn (II) ions solution concentrations (39.05, 86.66, 121.01, 155.23 and 191.27 mg L^?1), contact time (10, 20, 40, 60 and 80 min) and temperature (25, 35 and 45°C) were investigated. The adsorption of Mn (II) is highly pH-dependent and the optimum pH for the removal was found to be 4 for all types of carbon. The adsorption capacity of Mn (II) removal increased with increasing in initial concentration of Mn (II) ions in solution. Freundlich and Langmuir isotherm models fitted well the experimental data. Kinetics of adsorption showed that this reaction followed the pseudo-second order. The adsorption process is spontaneous under the experimental conditions. Activated carbons prepared from Coula edulis nut shells may be used efficiently at the removing of Mn (II) from aqueous solution.