چكيده لاتين
Given the necessity of removing pharmaceutical pollutants and their associated risks in aquatic environments, the elimination of tetracycline was selected as the focus of this study. For this purpose, a photocatalytic process was employed using a ternary nanocomposite Bi₂WO₆/TiO₂/ZIF-67, synthesized via a hydrothermal method. Experiments demonstrated that the photocatalyst Bi₂WO₆/TiO₂/ZIF-67 with 25 wt% TiO₂ and 10 wt% ZIF-67 exhibited the highest photocatalytic performance. To evaluate the synthesized photocatalyst, various characterization techniques, including XRD, FTIR, BET, PL, UV-vis DRS, XRF, FE-SEM, EDS, Mapping, TEM, Photocurrent, ICP-OES, and LC-MS, were utilized.The removal efficiency of tetracycline from aqueous solutions in a slurry system was examined under different operational factors, including pH, pollutant concentration, photocatalyst loading, and light intensity. Optimal conditions were determined to be pH = 7, a photocatalyst loading of 0.4 g/L, pollutant concentration of 10 ppm, and light intensity of 600 W/m², achieving 100% removal of tetracycline within 240 minutes.To address challenges associated with the slurry system, the photocatalyst was immobilized on conductive ITO glass for use in a fixed-bed thin-film photoreactor. The effects of operational parameters in the immobilized system, such as light intensity, residence time, and the photocatalyst-to-pollutant concentration ratio, were investigated. Optimal conditions, determined using the classical one-factor-at-a-time optimization method, included a photocatalyst-to-pollutant ratio (L/C) of 0.2 g per mg pollutant, a residence time of 100 minutes, pH = 7, and light intensity of 600 W/m². Under these conditions, the immobilized photocatalyst on ITO glass achieved a removal efficiency of 95%. Also, the stabilized state was compared under visible light and under sunlight, and the results showed improved removal efficiency under sunlight in a shorter time.
