Photochemical Degradation of Fluocinolone Acetonidin Drug in Aqueous Solutions Using Nanophotocatalyst ZnO Doped by C, N, and S

It has been shown that the photocatalytic activity of doped semiconductor with some nonmetals is higher than a pure semiconductor. Hence, with an attempt to achieve higher photocatalytic activity, doped ZnO with C, N, and S was prepared by a sedimentary process and used for the photocatalytic degradation of Fluocinolone Acetonidin as a drug in aqueous solutions.  X-Ray Diffraction (XRD), Energy Dispersion X-ray (EDX), X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM) were used to characterize the microstructure and morphology of the precursor and the products. The photocatalytic degradation of the drug was investigated using supported ZnO/C, N, and S photocatalyst under UV light irradiation. We also studied the influence of the basic photocatalytic parameters as well as irradiation time, the initial concentration of the drug, pH of the solution, amount of nanoparticles and addition of oxidant on the reaction. The optimum conditions of degradation were obtained accordingly: concentration of Fluocinolone Acetonidin,  20 ppm; the amount of photocatalyst, 7 mg; oxidant (K2S2O8), 5 mM; irradiation time, 6 h in  pH=9. Kinetic analysis demonstrated that the amount of Fluocinolone Acetonidin photocatalytic degradation can be fitted by a pseudo-first-order model.