Local, cheep and nontoxic activated carbon as efficient adsorbent for the simultaneous removal of cadmium ions and malachite green: Optimization by surface response methodology

The focus of present study is on the optimization of variables influencing the simultaneous removal of Cd2+ ion and malachite green (MG) from aqueous solution by activated carbon (AC). The AC was prepared from oak wood and then it was characterized using different techniques such as SEM, BET, FT-IR and Boehm titration. The effects of variables such as pH, initial dye concentration, cadmium ion concentration, adsorbent mass (g) and contact time on the adsorption of Cd2+ ion and MG were examined by central composite design (CCD). The experimental data for single solution of either of Cd2+ ion and MG followed the Langmuir model. The adsorption of Cd2+ ion in binary mixture followed the Freundlich model. The rate of adsorption and mass transfer kinetics exactly can be elucidated by pseudo second order model. (C) 2014 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.