title: The role of visible light active TiO2specimens on the solar photocatalytic disinfection of E. coli.
abstract: Solar photocatalytic disinfection efficiency of novel visible light activated (VLA) photocatalysts was evaluated with the aim of assessing inactivation of Escherichia coli as the pathogen indicator organism present in drinking water. Influence of humic acid (HA) on the photocatalytic disinfection efficiency of the specified VLA TiO2specimens i.e., N-doped, Se-doped, and Se-N co-doped TiO2was also investigated. Photocatalytic disinfection efficiency was assessed by the enumeration of bacteria following selected irradiation periods. Degradation and compositional changes in organic matter (OM) was also tracked by means of UV-vis and advanced fluorescence spectroscopic (EEM features) parameters. Photocatalytic mineralization of the organic matter was followed by dissolved organic carbon contents. Presence of HA as a model organic compound of natural organic matter (NOM) displayed a retardation effect on solar photocatalytic abatement of E. coli. However, no distinctly different effect was observed under solar photolytic conditions due to the presence of HA. Regrowth of E. coli could not be assessed under the specified experimental conditions. A comparison was introduced with respect to the use of undoped TiO2P-25 as the photocatalyst.
authors.affiliation: Institute of Environmental Sciences, Bogazici University, 34342 Bebek, Istanbul, Turkey. cemre.birben@boun.edu.tr.
authors.forename: Nazmiye Cemre
authors.initials: NC
authors.lastname: Birben
authors.affiliation: Institute of Environmental Sciences, Bogazici University, 34342 Bebek, Istanbul, Turkey.
authors.forename: Ayse
authors.initials: A
authors.lastname: Tomruk
authors.affiliation: Institute of Environmental Sciences, Bogazici University, 34342 Bebek, Istanbul, Turkey.
authors.forename: Miray
authors.initials: M
authors.lastname: Bekbolet
mesh_terms: D002384:Catalysis; D004203:Disinfection; D004926:Escherichia coli / Q000528:radiation effects*; D008027:Light; D013472:Sunlight; D014025:Titanium / Q000737:chemistry
chemical_list: C009495:titanium dioxide; D014025:Titanium
keywords: Disinfection; EEM; Photocatalysis; TiO2; Visible light active photocatalysts