Adsorption of 2,4-dichlorophenoxyacetic acid and carbofuran pesticides onto granular activated carbon

Adsorption equilibrium and kinetics of 2,4-dichlorophenoxyacetic acid (2,4-D) and carbofuran using commercial granular activated carbon, Filtersorb 300 (GAC F300) were studied in a batch system with respect to initial concentration of 2,4-D and carbofuran. The Langmuir and the Freundlich isotherm models were applied to the equilibrium data of 2,4-D and carbofuran adsorption. Observed results showed that the equilibrium data fitted well to the Langmuir equilibrium model in the studied concentration range of 2,4-D and carbofuran. The monolayer adsorption capacities of GAC F300 were 181.82 and 96.15 mg/g for 2,4-D and carbofuran, respectively. Two simplified models, pseudo-first order and pseudo-second order kinetic, were used to test the adsorption kinetics of 2, 4-D and carbofuran on GAC F300. The data was best fitted to the pseudo-second-order kinetic model. (C) 2010 Elsevier B.V. All rights reserved.