Removal of Bisphenol-A by Catalytic and Photocatalytic Ozonation Processes with Nano CeO2 Catalyst: Optimization Using a Central Composite Design

Abstract Bisphenol A (BPA) is an endocrine disrupting substance used in many manufacturing processes. It causes many negative effects on organisms in terrestrial and aquatic environments, such as estrogenicity, cytotoxicity, genotoxicity and carcinogenicity. Therefore, the treatment of BPA has gained importance recently. In this study, BPA removal from synthetic wastewater containing BPA by catalytic ozonation process (COP) and photocatalytic ozonation process (PCOP) was examined. Both processes have been optimized with the Central Composite Desing (CCD) method. BPA removals have been estimated in both processes with the developed second-order models. R 2 values in COP and PCOP are 0.9977 and 0.9942, respectively. So, the statistical significance of the models has been confirmed. When the optimum conditions for COP are pH 6.76, ozone dose 2244.09 mg/L, catalyst dose 45.38 mg/L, and reaction time 13.18 min, the maximum BPA removal efficiency is 98.84%. In PCOP, 99.97% BPA removal efficiency was found to be pH 6.91, ozone dose 1644.73 mg/L, catalyst dose 41.63 mg/L, light intensity 23.72 Watt and reaction time 14.36 min. Operating costs within COP and PCOP were calculated as $10.484 and $9.745 per m 3 , respectively. Reuse tests have shown that the catalyst can be used repeatedly with minimal loss of efficiency. In inhibitor tests, the dominant radical in both processes was determined as ° OH. This study reveals that BPA can be removed with high efficiency and low cost using COP and PCOP. Graphical Abstract