Investigation of Adsorption of Cu (II) Heavy Metal with Bentonite

Abstract

In this study, adsorption of undesirable Cu (II) ion with bentonite in industrial wastewater was investigated at different temperature, pH and time intervals. Adsorption experiments were started with an adsorbent amount of 0.5 grams. Optimum pH determination experiments were carried out in the first stage of the adsorption experiments. The optimum pH determined after the experiments was determined as 5.0. Adsorption rates and adsorbed metal ions concentration increased with increasing concentrations of starting Cu (II) ions up to 25 mg / L and 500 mg / L in a medium containing 0.5 g of adsorbent. In the isotherm studies, isotherms were plotted and isotherm constants were calculated and it was clearly observed that the adsorption system, Langmuir and Freundlich isotherms. When the Gibbs free energy (ΔG) values calculated at different temperatures are taken into consideration, it is observed that the Cu (II) ions have negative values, for 100 mg/L and lower especially at low concentrations, and thus the reactions take place spontaneously for these concentrations. The compatibility of the adsorption system with the Langmuir and Freundlich isotherms was investigated, and it was observed that the adenomatoid system adhered to Langmuir and Freundlich. Based on the results, it is concluded that the amount of metal retained on the surface increases with temperature increase. Values (n> 1) were obtained for the experiments performed at each concentration of Cu (II) ions (up to 500 mg / L at 25 mg / L).