PHOTOCATALYTIC DEGRADATION OF 17P-ESTRADIOL UNDER SOLAR IRRADIATION

摘要

Natural steroid 17β-estradiol (E2) is one of endocrine disrupting chemicals (EDCs). Estrogenic steroids are detected in both the influent and effluent of sewage treatment plants in different countries at various concentrations. Among the various environmental degradation processes (abiotic/ biotic), photodegradation under solar irradiation is one of the most important factors for determining the ultimate fate of the persistent pollutants in aquatic environments. In this research, TiO2 prepared by sol-gel method achieve nano particle size about 30 nm can improve photodegradation rate constant of E2. Photocatalytic degradation of E2 by TiO2 under solar irradiation can increase rate constant (k = 2.20-2.42 hr~(-1)) and mineralization (65-95% after 5 hr irradiation). The E2 photodegradation followed pseudo-first-order kinetics, with the rate constant increasing slightly with increased pH. In the presence of NO3~- the photodegradation rate increased significantly, attributed to photosensitization by the reactive species.