title: Photocatalytical removal of fluorouracil using TiO2-P25 and N/S doped TiO2catalysts: A kinetic and mechanistic study.
abstract: In the present study, the photocatalytic activity of TiO2-based photocatalysts toward degradation and mineralization of the anti-cancer drug 5-fluorouracil (5-FU) in aqueous phase was investigated under simulated solar and visible irradiation. Commercial TiO2(P25) and N/S-doped TiO2catalysts synthesized by a simple sol-gel method were used as photocatalysts. TiO2P-25 was found to be the most photoactive catalyst for the removal of 5-FU, under simulated solar irradiation. Among N/S-doped TiO2catalysts, the one with molar Ti:N/S ratio equal to 0.5 was the most efficient under simulated solar irradiation. In contrast, under visible irradiation the catalyst with equimolar Ti:N/S ratio showed the highest performance for the removal of 5-FU. Scavenging experiments revealed that HO radicals and h+were the major reactive species mediating photocatalytic degradation of 5-FU using TiO2P-25 and N/S-doped TiO2catalysts, under simulated solar irradiation. On the other hand, the essential contribution of1O2and O2-in the degradation of 5-FU under visible light was proved. The transformation products (TPs) of 5-FU, were identified by LC-MS-TOF suggesting that defluorination followed by hydroxylation and oxidation are the main transformation pathways, under all the studied photocatalytic systems.
authors.affiliation: Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
authors.forename: Α
authors.initials: Α
authors.lastname: Koltsakidou
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100 Agrinio, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Antonopoulou
authors.affiliation: Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
authors.forename: Ε
authors.initials: Ε
authors.lastname: Εvgenidou
authors.affiliation: Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: I
authors.initials: I
authors.lastname: Konstantinou
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100 Agrinio, Greece.
authors.forename: A E
authors.initials: AE
authors.lastname: Giannakas
authors.affiliation: Department of Environmental and Natural Resources Management, University of Patras, 30100 Agrinio, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Papadaki
authors.affiliation: Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
authors.forename: D
authors.initials: D
authors.lastname: Bikiaris
authors.affiliation: Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece. Electronic address: dlambro@chem.auth.gr.
authors.forename: D A
authors.initials: DA
authors.lastname: Lambropoulou
mesh_terms: D002384:Catalysis; D005472:Fluorouracil / Q000302:isolation & purification*; D008027:Light; D010782:Photolysis; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D014025:Titanium; D005472:Fluorouracil
keywords: 5-Fluorouracil; N/S-doped TiO(2) catalysts; Scavengers; TiO(2); Transformation products