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Disinfection of natural water by solar photocatalysis using immobilized TiO2 devices / Asunción Acevedo in Transactions of the ASME. Journal of solar energy engineering, Vol. 133 N° 1 (Fevrier 2011) 

Public ISBD [article]  in Transactions of the ASME. Journal of solar energy engineering > Vol. 133 N° 1 (Fevrier 2011) . - 10 p. Titre : Disinfection of natural water by solar photocatalysis using immobilized TiO2 devices : efficiency in eliminating indicator bacteria and operating life of the system Type de document : texte imprimé Auteurs : Asunción Acevedo, Auteur ; Edward A. Carpio, Auteur ; Juan Rodriguez, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Solar energy Langues : Anglais (eng) Mots-clés : Catalysis  Microorganisms  Photochemistry  Sol-gel  processing  Titanium  compounds  Water  treatment Index. décimale : 621.47 Résumé : Natural water has been disinfected using TiO2 as the fixed catalyst incorporated in a homemade photoreactor, in which the dimensions and the design parameters are representative of devices that are currently employed at larger scale. The catalyst was immobilized on the external surface of a cylinder of frosted glass situated in the longitudinal axis of a tubular glass reactor. Two alternative methods of immobilizing the catalyst on glass were studied: in the first, a commercial titanium oxide powder (Aeroxide® TiO2 P25) was mounted on a polymeric support; and in the second, it was applied by sol-gel deposition. Illumination was effected by installing the glass reactor in the irradiation chamber of a solar simulator. Under laboratory conditions, groundwater contaminated with cultured and wild bacteria was treated photocatalytically, and the influence of the photolysis, the pumping, and the catalysts was studied. The results obtained have demonstrated that the catalyst immobilized in the interior of the photoreactor presents similar results, in the disinfection of E. coli, as 0.5 g/l of TiO2 P25; and that, in 1.5 h approximately of simulated solar illumination (167 kWUVA s/m2) on the sol-gel deposit of TiO2, it is possible to eliminate 100% of the bacteria covered by international regulations in respect of water for human consumption. With regard to the aging assay of the system, it was observed at 250 h of operation a reduction in the effectiveness of the disinfection process. At 0 and 250 h of operation, the percentages of elimination of E. coli after 50 min of illumination were 100% and 99.5%, respectively. This reduction in the effectiveness of the process was due to the formation of a film of calcium carbonate adhering to the internal glass wall of the photoreactor, which is in contact with the liquid being treated, and to the presence of calcium carbonate precipitates on catalyst surface. DEWEY : 621.47 ISSN : 0199-6231 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000134000001 [...] [article] Disinfection of natural water by solar photocatalysis using immobilized TiO2 devices : efficiency in eliminating indicator bacteria and operating life of the system [texte imprimé] / Asunción Acevedo, Auteur ; Edward A. Carpio, Auteur ; Juan Rodriguez, Auteur . - 2012 . - 10 p. Solar energy Langues : Anglais (eng) in Transactions of the ASME. Journal of solar energy engineering > Vol. 133 N° 1 (Fevrier 2011) . - 10 p. Mots-clés : Catalysis  Microorganisms  Photochemistry  Sol-gel  processing  Titanium  compounds  Water  treatment Index. décimale : 621.47 Résumé : Natural water has been disinfected using TiO2 as the fixed catalyst incorporated in a homemade photoreactor, in which the dimensions and the design parameters are representative of devices that are currently employed at larger scale. The catalyst was immobilized on the external surface of a cylinder of frosted glass situated in the longitudinal axis of a tubular glass reactor. Two alternative methods of immobilizing the catalyst on glass were studied: in the first, a commercial titanium oxide powder (Aeroxide® TiO2 P25) was mounted on a polymeric support; and in the second, it was applied by sol-gel deposition. Illumination was effected by installing the glass reactor in the irradiation chamber of a solar simulator. Under laboratory conditions, groundwater contaminated with cultured and wild bacteria was treated photocatalytically, and the influence of the photolysis, the pumping, and the catalysts was studied. The results obtained have demonstrated that the catalyst immobilized in the interior of the photoreactor presents similar results, in the disinfection of E. coli, as 0.5 g/l of TiO2 P25; and that, in 1.5 h approximately of simulated solar illumination (167 kWUVA s/m2) on the sol-gel deposit of TiO2, it is possible to eliminate 100% of the bacteria covered by international regulations in respect of water for human consumption. With regard to the aging assay of the system, it was observed at 250 h of operation a reduction in the effectiveness of the disinfection process. At 0 and 250 h of operation, the percentages of elimination of E. coli after 50 min of illumination were 100% and 99.5%, respectively. This reduction in the effectiveness of the process was due to the formation of a film of calcium carbonate adhering to the internal glass wall of the photoreactor, which is in contact with the liquid being treated, and to the presence of calcium carbonate precipitates on catalyst surface. DEWEY : 621.47 ISSN : 0199-6231 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000134000001 [...]

Disinfection of natural water by solar photocatalysis using immobilized TiO2 devices: efficiency in eliminating Indicator bacteria and operating life of the system / Asunción Acevedo in Transactions of the ASME. Journal of solar energy engineering, Vol. 134 N° 1 (Janvier/Fevrier 2012) 

Public ISBD [article]  in Transactions of the ASME. Journal of solar energy engineering > Vol. 134 N° 1 (Janvier/Fevrier 2012) . - 10 p. Titre : Disinfection of natural water by solar photocatalysis using immobilized TiO2 devices: efficiency in eliminating Indicator bacteria and operating life of the system Type de document : texte imprimé Auteurs : Asunción Acevedo, Auteur Année de publication : 2012 Article en page(s) : 10 p. Note générale : Solar energy Langues : Anglais (eng) Mots-clés : Catalysis,  Microorganisms,Photochemistry,  Sol-gel  processing,  Titanium  compounds,  Water  treatment Résumé : Natural water has been disinfected using TiO2 as the fixed catalyst incorporated in a homemade photoreactor, in which the dimensions and the design parameters are representative of devices that are currently employed at larger scale. The catalyst was immobilized on the external surface of a cylinder of frosted glass situated in the longitudinal axis of a tubular glass reactor. Two alternative methods of immobilizing the catalyst on glass were studied: in the first, a commercial titanium oxide powder (Aeroxide® TiO2 P25) was mounted on a polymeric support; and in the second, it was applied by sol-gel deposition. Illumination was effected by installing the glass reactor in the irradiation chamber of a solar simulator. Under laboratory conditions, groundwater contaminated with cultured and wild bacteria was treated photocatalytically, and the influence of the photolysis, the pumping, and the catalysts was studied. The results obtained have demonstrated that the catalyst immobilized in the interior of the photoreactor presents similar results, in the disinfection of E. coli, as 0.5 g/l of TiO2 P25; and that, in 1.5 h approximately of simulated solar illumination (167 kWUVA s/m2) on the sol-gel deposit of TiO2, it is possible to eliminate 100% of the bacteria covered by international regulations in respect of water for human consumption. With regard to the aging assay of the system, it was observed at 250 h of operation a reduction in the effectiveness of the disinfection process. At 0 and 250 h of operation, the percentages of elimination of E. coli after 50 min of illumination were 100% and 99.5%, respectively. This reduction in the effectiveness of the process was due to the formation of a film of calcium carbonate adhering to the internal glass wall of the photoreactor, which is in contact with the liquid being treated, and to the presence of calcium carbonate precipitates on catalyst surface. DEWEY : 621.47 ISSN : 0199-6231 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000134000001 [...] [article] Disinfection of natural water by solar photocatalysis using immobilized TiO2 devices: efficiency in eliminating Indicator bacteria and operating life of the system [texte imprimé] / Asunción Acevedo, Auteur . - 2012 . - 10 p. Solar energy Langues : Anglais (eng) in Transactions of the ASME. Journal of solar energy engineering > Vol. 134 N° 1 (Janvier/Fevrier 2012) . - 10 p. Mots-clés : Catalysis,  Microorganisms,Photochemistry,  Sol-gel  processing,  Titanium  compounds,  Water  treatment Résumé : Natural water has been disinfected using TiO2 as the fixed catalyst incorporated in a homemade photoreactor, in which the dimensions and the design parameters are representative of devices that are currently employed at larger scale. The catalyst was immobilized on the external surface of a cylinder of frosted glass situated in the longitudinal axis of a tubular glass reactor. Two alternative methods of immobilizing the catalyst on glass were studied: in the first, a commercial titanium oxide powder (Aeroxide® TiO2 P25) was mounted on a polymeric support; and in the second, it was applied by sol-gel deposition. Illumination was effected by installing the glass reactor in the irradiation chamber of a solar simulator. Under laboratory conditions, groundwater contaminated with cultured and wild bacteria was treated photocatalytically, and the influence of the photolysis, the pumping, and the catalysts was studied. The results obtained have demonstrated that the catalyst immobilized in the interior of the photoreactor presents similar results, in the disinfection of E. coli, as 0.5 g/l of TiO2 P25; and that, in 1.5 h approximately of simulated solar illumination (167 kWUVA s/m2) on the sol-gel deposit of TiO2, it is possible to eliminate 100% of the bacteria covered by international regulations in respect of water for human consumption. With regard to the aging assay of the system, it was observed at 250 h of operation a reduction in the effectiveness of the disinfection process. At 0 and 250 h of operation, the percentages of elimination of E. coli after 50 min of illumination were 100% and 99.5%, respectively. This reduction in the effectiveness of the process was due to the formation of a film of calcium carbonate adhering to the internal glass wall of the photoreactor, which is in contact with the liquid being treated, and to the presence of calcium carbonate precipitates on catalyst surface. DEWEY : 621.47 ISSN : 0199-6231 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000134000001 [...]