Adsorptive Removal of Phenol from Aqueous Solution Using Activated Carbon Prepared from Babul Sawdust

Abstract

Study on the adsorption of phenol onto activated carbon prepared from Babul (Acacia nilotica) sawdust (BAC), a waste from sawmill, is presented in this paper. The effect of various parameters such as adsorbent dose (m), initial pH (pH0), contact time (t), initial concentration (Co), and temperature (T) on adsorption capacity of BAC was tested using batch adsorption experiments. The kinetic study was performed by using different kinetic models, viz pseudo first, pseudo second order, and intraparticle diffusion. Langmuir, Freundlich, Redlich-Peterson, and Temkin isotherm equations were used to find the suitable and well-describing experimental isotherm data. The adsorption of phenol onto BAC follows the pseudo second order kinetic model, and equilibrium adsorption data follow the Redlich-Peterson and Freundlich isotherm equation. The maximum removal of phenol was found to be about 83% for the initial concentration of 50 mg/L and about 50% for the higher initial concentration of 500 mg/L at 10 kg/m3 of BAC dose and normal temperature of 303 K. Thermodynamic study illustrates that the adsorption of phenol onto BAC is a completely exothermic, spontaneous process, and the adsorption decreases with the increase in temperature.