Micro-TiO2 coated glass surfaces safely abate drugs in surface water

The ingredients of Pharmaceuticals and Personal Care Products (PPCPs) persist in water and conventional treatment plants are not able to remove them efficiently. Sonochemical treatment is insufficient to mineralize organics such as ibuprofen into CO2 and H2O. TiO2 degrades ibuprofen (IBP) under UV light; however, it does not reach a high grade of conversion. Here, we investigated the mineralization of ibuprofen to CO2 by TiO2 UV-C photocatalysis. We replaced nano-sized P25 (the standard catalyst) with a micro-sized commercial sample of TiO2 to preclude the use of nanoparticles which are dangerous for human health and because typical filtration systems are expensive and inefficient. We deposited micro-TiO2 on glass Raschig rings to ensure an easy recovery and reuse of the photocatalyst and we studied its performance both with a batch and a continuous reactor. Micro-TiO2 mineralized 100% of IBP in 24 h. TiO2-coated glass Raschig rings degraded 87% of IBP in 6 h of UV-C irradiation in a continuous reactor, with a mineralization of 25%. Electronspray ionization mass spectrometer (ESI-MS, positive mode) analyses identified 13 different byproducts and we hypothised a degradration pathway for IBP degradation.