METHYLENE BLUE ADSORPTION FROM AQUEOUS SOLUTION USING ACTIVATED CARBON PREPARED FROM OLIVE BAGASSE

In this study, activated carbon was prepared from olive bagasse by chemical activation with phosphoric acid, and the prepared activated carbon was used to remove methylene blue from aqueous solutions. The surface area and total pore volume of chemically modified activated carbon were 036 m(2)/g and 0.598 cm(3)/g, respectively. The effects of various experimental parameters, such as pH, contact time, temperature and the amounts of adsorbent, were investigated in batch adsorption. The experimental data indicated that the adsorption isotherms are well described by the Langmuir equilibrium isotherm equation and the calculated adsorption capacity of activated carbon was 88.49 mg/g at 45 degrees C. The maximum adsorption capacities onto activated carbon at 25, 35 and 45 degrees C were found to be 71.43, 73.53, and 88.49 mg/g, respectively. The pseudo first-order, pseudo second-order and intra-particle diffusion kinetic models were used to describe the kinetic data, and the rate constants were evaluated as well. The experimental data fitted very well to pseudo second-order kinetic model. The thermodynamic parameters, such as Delta G degrees, Delta H degrees and Delta S degrees, were calculated to,stimate the nature of adsorption.