Adsorption of 2,4,6-trichlorophenol from aqueous solution onto activated carbon derived from loosestrife Original Research Article

An activated carbon was prepared from the stalk of the scrap aquatic plant loosestrife, by H3PO4 activation and then was evaluated for its ability to adsorb 2,4,6-trichlorophenol (TCP). The effects of solution pH, agitation time, TCP initial concentration, and temperature on TCP adsorption were investigated. The equilibrium adsorption data of TCP on activated carbon were analyzed by Langmuir, Freundlich and Temkin isotherm models. The Temkin model gave the best correlation with the experimental data. The adsorption was found to follow the pseudo-second-order kinetics. The intraparticle diffusion model was used to determine the mechanism of the adsorption process. Thermodynamic parameters such as standard enthalpy (ΔHo), standard entropy (ΔSo), and standard free energy (ΔGo) were obtained. Adsorption of TCP is exothermic with ΔHo at −12.87 kJ/mol.