Modified Mangosteen Shell in the Removal of Hg (II) from Aqueous Solution-Isotherm and Kinetic Studies

Abstract

An activated carbon was prepared from an agricultural waste mangosteen shell by chemical modification (BTMC) and removal efficiency was tested using aqueous solution of Hg (II). The functional groups and surface morphology of BTMC were analyzed using FT-IR and SEM studies. Commercial activated carbon (CAC) was used to compare the efficiency of BTMC in Hg (II) removal. Batch mode studies were conducted to evaluate the parameters like contact time, pH, carbon dose on the removal efficiency of Hg (II) from aqueous solution. Removal of mercury occurs at optimal contact time of 120 min at pH 5 and carbon dosage of 120 mg for BTMC. Adsorption isotherm was studied using Freundlich, Langmuir, and Temkin isotherm models. Equilibrium data fitted well with Langmuir isotherm. The maximum adsorption capacity of Hg (II) was found to be 49.75 mg g-1 for BTMC. The pseudo second-order kinetic model fits well with the experimental data. Wastewater analysis was also performed to evaluate the practical applicability of the carbon.