Adsorption of Cr(VI) from aqueous phase by high surface area activated carbon prepared by chemical activation with ZnCl2

Prepared activated carbon from fox nutshell by chemical activation with ZnCl2 in the N-2 atmosphere was used for Cr(VI) removal from aqueous solution. Activated carbon was produced at 600 degrees C activation temperature with a 2.0 impregnation ratio for 1 h of activation time has been found as 2869 m(2)/g, 1.96 and 1.68 cm(3)/g of highest BET surface area, total pore volume and micropore volume, respectively. Batch mode adsorption studies were carried out by varying agitation speed, pH, temperature, agitation time and initial Cr(VI) concentration. The adsorption of Cr(VI) was pH dependent and showed maximum removal efficiency of Cr(VI) at pH 2.0. Adsorption studies of 10-25 mg/L initial Cr(VI) concentration were conducted at pH of 2.0 and temperature of 30 degrees C. The equilibrium, kinetics, and thermodynamics of Cr(VI) adsorption were studied. The adsorption capacity of Cr(VI) from the synthetic wastewater was 43.45 mg/g. The experimental adsorption equilibrium data was fitted to Langmuir adsorption model with an adequate adsorption capacity of 46.21 mg/g. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.