Photocatalytic degradation of β-blockers by using immobilized titania/silica on glass slides

Publication date: Available online 3 March 2015 Source:Journal of Photochemistry and Photobiology A: Chemistry Author(s): Veronika Píšťková , Minoo Tasbihi , Milada Vávrová , Urška Lavrenčič Štangar Photocatalytic degradation of five β-blockers (acebutolol, atenolol, metoprolol, nadolol and propranolol) was investigated in aqueous media using immobilized TiO2 as a photocatalyst. The analyzed parameters were pharmaceutical removal and non purgable organic carbon. Two different types of photocatalyst incorporated in sol-gel matrix were compared; P25 exhibited a higher photocatalytic activity compared to P90 (both from Evonik Degussa). Besides, optimal photocatalyst concentration and light intensity were determined. According to the results obtained, after 120min of treatment a complete removal was achieved for all compounds (initial concentration 25mg/L) using P25. After 240min of irradiation a mineralization degree ranged from 75 % for acebutolol to 92% for propranolol. A longer illumination time was needed for complete removal of β-blockers in river water. Main intermediate compounds were identified by high performance liquid chromatography coupled to mass spectrometry (HPLC-MS/MS) technique. Graphical abstract
Source: Journal of Photochemistry and Photobiology A: Chemistry - Category: Chemistry Source Type: research