Copper Removal by Acid-Conditioned Zeolite, Part Ii: Kinetics, and Thermodynamic Studies

Abstract

Heavy metal water pollution is one of the most pressing environmental problems of the last decades. Wastewater from many industrial processes contain high concentrations of metals and have very acid pH. Thus, technologies to remove heavy metals from aqueous solutions are costly or suffer deterioration when in contact with substances with acid pH. Natural zeolites have demonstrated to be a low-cost heavy metal adsorbent. This study aimed to determine basic parameters for efficient copper removal by aluminosilicates. A Zeolite was conditioned with concentrated H₂SO₄ to further develop the experiments to test 4 kinetics (Pseudo-first-order, Pseudo-second-order, Elovich and Webber-Morris) and to calculate thermodynamic parameters (ΔG°, ΔH°, ΔS° and Ea). Out of the studied kinetic models, the one that best correlated was the Pseudo-second order model. According to thermodynamic studies, the increase in temperature favors adsorption and the process is spontaneous.

Keywords: Kinetics, Thermodynamic, Aluminosilicates, Metals, Pseudo-second-order.

DOI: 10.7176/JEES/9-3-04

Publication date:March 31^st 2019