Adsorption of phenol and substituted chlorophenols from aqueous solution by activated carbon prepared from jackfruit (artocarpus heterophyllus) peel-kinetics and equilibrium studies

This study is aimed at the effectiveness of an adsorbent prepared from jackfruit peel (artocarpus heterophyllus), an agricultural waste, for the removal of phenol, 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol from aqueous solutions. Batch adsorption experiments were carried out as a function of solution pH, contact time, phenol concentration, adsorbent dose, and temperature. The adsorption equilibrium was reached in 5 h. The order of removal was found to be 2,4-dichlorophenol > 4-chlorophenol > 2-chlorophenol > phenol. The Freundlich and Langmuir isotherm models were applied to the equilibrium data. The maximum sorption capacities for phenol, 2-chlorophenol, 4-chlorophenol, and 2,4-dichlorophenol were found to be 144.9 mg/g, 243.9 mg/g, 277.7 mg/g, and 400.0 mg/g respectively. The removal of phenols was found to be most effective at lower pH. Kinetic data of the adsorption process could fit a pseudo second order rate equation. An attempt was also made to understand the mechanism of phenol adsorption. The results reveal that the activated carbon prepared can be economical for the removal of phenols compared to many other reported adsorbents.