Adsorption of mercury (II) ion from aqueous solution using low‐cost activated carbon prepared from mango kernel. Issue 1 (7th February 2012) - Somayajula, Anusha
ABSTRACT A low‐cost activated carbon (AC) was prepared from mango kernel through chemical activation with ZnCl2. The adsorption capacity of AC was investigated for the removal of Hg(II) from aqueous solution as batch experiments using varying initial adsorbent dosage, pH, equilibrium time and temperature. The prepared AC had a Brunauer‐Emmett‐Teller surface area of 920 m2 g−1 and total pore volume of 0.341 cm3 g−1, respectively. A maximum removal of 92% was achieved with an initial Hg(II) concentration of 10 mg L−1, pH 6.5 and adsorbent dose of 3 g L−1. The obtained kinetic experimental data were fitted to pseudo‐first‐order, pseudo‐second‐order and intraparticle diffusion models, respectively. Among the models, the pseudo‐second‐order adsorption model was found to fit better, with a coefficient of regression (R2) > 0.95. The equilibrium data were also fitted to the Langmuir and Freundlich equilibrium isotherm models. Both the models were found to provide a better fitting with coefficient of regression (R2) > 0.98. The enthalpy of adsorption was found to be 7.2 kJ mol−1. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.