Mineralization of bisphenol A by advanced oxidation processes

BACKGROUND: Endocrine disruptors, as in the case of bisphenol A (BPA), are increasingly found in aqueous effluents. The degree of mineralization of a bisphenol A (BPA) aqueous solution after applying several oxidation treatments has been investigated. RESULTS: UV‐C photolysis of BPA allowed calculation of the quantum yield, ?_λ=254 = 0.045 ± 0.005 mol Einstein^?1 but only 15% of the initial organic carbon content (TOC) was eliminated. Better results (80% conversion) were obtained after TiO₂ addition. Ozone inmediately reacts with BPA. Again, TiO₂ addition in the presence of O₃ was capable of increasing the mineralization level (60%). The photolytic ozonation of BPA was capable of completely eliminating TOC. The presence of activated carbon in the O₃/UV and O₃/UV/TiO₂ systems significantly enhanced the TOC removal reaction rate (100% conversion in 20 min). CONCLUSIONS: Processes such as ozonation or photolysis are capable of efficiently removing BPA from water however, mineralization levels are rather low. Addition of TiO₂ to O₃ or UV‐C significantly enhances TOC removal. The remaining organics still account for an average 20–40% of the initial organic carbon. The combination of O₃/UV‐C is capable of completely mineralizing BPA. Activated carbon and/or TiO₂ addition to the system O₃/UV‐C improves the TOC depletion rate. Copyright © 2008 Society of Chemical Industry