Oxidative degradation of bisphenol A and 17α-ethinyl estradiol by Fenton-like activity of silver nanoparticles in aqueous solution.

Silver nanoparticles (AgNPs) have been reported to have antibacterial activities and cytotoxicity, resulting from the dissolved silver cation (Ag) and its soluble complexes. However, to our knowledge, little has been reported about their potential use in degrading organic contaminants such as endocrine-disrupting compounds in aqueous solution. In this first report on the subject, we examined the effectiveness of the oxidative degradation of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) in water by reactive oxygen species formed during the decomposition of HO, assisted by polyvinylpyrrolidone (PVP)-stabilized AgNPs. The dissolution of AgNPs accompanied generation of OH at low pH. The fully dispersed PVP-AgNPs in the presence of HO exhibited fast degradation kinetics for EE2 at a typical aquatic condition of pH (6-7). The oxidation kinetics of BPA and EE2 by PVP-AgNPs can be interpreted using three different modeling approaches: an initial pseudo-first-order, a retarded first-order rate, and Behnajady-Modirshahla-Ghanbery kinetic equation. The findings showed that AgNPs may have potential to facilitate the in situ oxidation for emerging contaminants in the aqueous environment.