Adsorption of Phenol From Aqueous Solutions Using Activated Carbon Prepared From Crofton Weed

Abstract:Activated carbon from crofton weed (ACCW) was evaluated for its ability to remove phenol from aqueous solutions. Batch experiments were used to examine kinetics, adsorption isotherm, pH effect, and thermodynamic parameters. Adsorption data for phenol uptake by ACCW were analyzed according to Langmuir, Freundlich and Temkin adsorption models. Thermodynamic parameters for the adsorption system were determinated at 293 K, 313 K and 333 K (ΔH° = −22.92 kJ mol⁻¹; ΔG^O = −2.87 to −5.28 kJ mol⁻¹ and ΔS^O = −60.20 J K⁻¹ mol⁻¹). ΔG° values obtained were negative, indicating that the adsorption of the phenol on the surface of ACCW was a spontaneous adsorption process. The kinetics of this process was described very well by a pseudo-second-order rate equation. These results show that the ACCW could be considered as a potential adsorbent for phenol in aqueous solutions.