Nobel Materials (ZnO Nanoparticles and ZnO Nanoparticles Supported on a Zeolite) for the Removal of Tartrazine from Aqueous Solutions

Abstract

Two materials (ZnO nanoparticles (nanZnO) and a composite (Ze-nanZnO)) were prepared; the composite was prepared by chemical precipitation on a natural zeolite. The materials were characterized by Xray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy (UV-Vis), and Branauer-Emmett-Teller (BET) surface area. These materials were evaluated for the removal of tartrazine; this dye was used because it is considered a dangerous contaminant. All experiments were done in batch process. The effect of different parameters such as the contact time, the initial dye concentration, and pH, in addition to the thermodynamic parameters, were studied in order to determine the best experimental conditions. The nanZnO shows a higher adsorption capacity than the Ze-nanZnO composite; however, the separation of the phases was difficult when nanoparticles were used. According to the kinetic data, the mechanism for the nanZnO is physisorption and for the Ze-nanZnO composite is chemisorption. The results show that this is a useful technique for the removal of this dye.