An innovative combination of electrochemical and photocatalytic processes for decontamination of bisphenol A endocrine disruptor form aquatic phase: Insight into mechanism, enhancers and bio-toxicity assay

Abstract

In the present study, an innovative combination of electrochemical and photocatalytic processes with significant synergy was considered to destroy bisphenol A (BPA) as model endocrine disrupting compound. For this purpose, in situ electro-generated ZnO nanoparticles due to the corrosion of sacrificial Zn anode played the photocatalyst role under visible light irradiation. X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Brunnaer–Emmett–Teller (BET), photoluminescence (PL) and UV–Vis diffuse reflectance spectra (DRS) results exhibited the formation of ultrafine crystalline ZnO nanoparticles with appropriate optical properties. A higher synergy factor was obtained by the combination of aforementioned electrochemical and photocatalytic processes relying on the electro-generated ZnO nanoparticles in BPA-contained solution. In the presence of chemical enhancing compounds such as solid hydrogen peroxide and Oxone, the degradation of BPA increased from 84 to 90.5 and 97.5% within 2 h, respectively. The complete elimination of BPA was attained during the elapsed time of 90 min when ultrasound was applied. The results of bio-toxicity assay, based on the application of biosolids as the source of living microorganisms, revealed that the hybrid process could decrease the specific oxygen consumption inhibition (ISOUR) of the BPA from 31.3 to 18.8%.