HEXAVALENT CHROMIUM REMOVAL FROM AQUEOUS SOLUTION VIA ADSORPTION ON GRANULAR ACTIVATED CARBON: ADSORPTION, DESORPTION, MODELING AND SIMULATION STUDIES
Hexavalent chromium is one of the contaminants recognized as a carcinogenic and mutagenic agent. Therefore, it is essential to remove it from wastewater before disposal. In this study, removal of hexavalent chromium via adsorption on commercial granular activated carbon (GAC) was investigated as a function of adsorbent dosage, initial solution pH, initial Cr (VI) concentration, contact time and temperature. The batch experiments were conducted at three temperatures (17, 27 and 37°C) and the
... d 37°C) and the results showed that Cr (VI) removal kinetics obeys pseudo second order rate equation. Equilibrium studies showed that the experimental data fitted well with Longmuir isotherm adsorption model. Thermodynamic parameters were also determined and results suggest that the adsorption process is a spontaneous and endothermic. Reversibility of Cr (VI) adsorption and repeated availability performance of the adsorbent, was investigated by desorption process. In addition, artificial neural network (ANN) was utilized to simulate the experimental data. The results showed that the training step of the network was successful and therefore the simulation could be applied to predict hexavalent chromium removal with high accuracy.