Solar photocatalysis as a final step for 17β-estradiol removal in domestic wastewater effluent.

Photodegradation of the natural steroid 17β-estradiol (E2), an endocrine disrupting hormone, which is commonly found into aquatic environments, was investigated by Advanced Oxidation Processes. Heterogeneous photocatalysis using titanium dioxide (TiO2) and photo-Fenton using peroxymonopersulfate (Oxone or PMS) are considered as forceful and environmental friendly processes that can be used as tertiary treatment stage to remove recalcitrant contaminants present in treated wastewater effluent. Our work focuses on the evaluation of E2 degradation using this processes. For an initial E2 concentration of 1.3±0.4 mg/L, either a 2:1 ratio of peroxymonosulfate:metal (Fe2+) or 0.7g/L of TiO2 were used. Independently of the oxidation method assessed, the decomposition of E2 always followed a pseudo-first order kinetic. By-products identified during the oxidation of E2 correspond to those described in the literature. The estrogenic activity test proved that molecules inducing the estrogenic activity were destroyed