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Characterization and vsible light photocatalytic activity of cerium- and Iron-doped titanium dioxide sol−gel materials / Meera Sidheswaran in Industrial & engineering chemistry research, Vol. 48 N° 23 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10292–10306 Titre : Characterization and vsible light photocatalytic activity of cerium- and Iron-doped titanium dioxide sol−gel materials Type de document : texte imprimé Auteurs : Meera Sidheswaran, Auteur ; Lawrence L. Tavlarides, Auteur Année de publication : 2010 Article en page(s) : pp. 10292–10306 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Characterization--Visible--Photocatalytic--Cerium--Iron-Doped--Titanium  Dioxide--Sol−Gel  Materials Résumé : Cerium- and iron-based titanium dioxide catalysts are made at varying concentrations and cured at different temperatures to develop a new class of photocatalysts that displays catalytic activity for volatile organic compound destruction when irradiated with visible light. These catalysts are characterized using X-ray diffractometry, Raman spectroscopy, UV−vis diffuse reflectance spectroscopy and BET surface area analyses. The potential of these catalysts to destroy indoor air volatile organics is evaluated using a tubular reactor flow channel with visible light irradiated interior surfaces through which air contaminated with toluene, decane, ethanol, acetaldehyde, or linalool is reacted. It was found that both cerium- and iron-doped titania have lower band-gap energy than pure titania and can be activated with visible light. The anatase and rutile phase transitions of these doped titania is however similar to pure titania and is unaffected by dopants. The crystalinity is however altered and crystal sizes in the range of six to nine nanometers were obtained with the sol−gel type synthesis of the titania catalyst. Although both cerium- and iron-based titania show destruction of these volatile organics in visible light as compared to pure titania, cerium-based titania has better performance than iron-based titania. A photocatalytic oxidation reaction pathway for linalool is proposed on the basis of previous studies and compounds are identified in the exit stream of the reactor. Further, reaction rate constants for toluene, linalool, ethanol, and acetaldheyhde have been determined using a two-dimensional diffusion model (Sidheswaran and Tavlarides, 2008), and are compared with values from literature. It has been found that cerium-doped titania developed in this study performs comparably to the commercially available titania even when irradiated with visible light. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900773m [article] Characterization and vsible light photocatalytic activity of cerium- and Iron-doped titanium dioxide sol−gel materials [texte imprimé] / Meera Sidheswaran, Auteur ; Lawrence L. Tavlarides, Auteur . - 2010 . - pp. 10292–10306. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10292–10306 Mots-clés : Characterization--Visible--Photocatalytic--Cerium--Iron-Doped--Titanium  Dioxide--Sol−Gel  Materials Résumé : Cerium- and iron-based titanium dioxide catalysts are made at varying concentrations and cured at different temperatures to develop a new class of photocatalysts that displays catalytic activity for volatile organic compound destruction when irradiated with visible light. These catalysts are characterized using X-ray diffractometry, Raman spectroscopy, UV−vis diffuse reflectance spectroscopy and BET surface area analyses. The potential of these catalysts to destroy indoor air volatile organics is evaluated using a tubular reactor flow channel with visible light irradiated interior surfaces through which air contaminated with toluene, decane, ethanol, acetaldehyde, or linalool is reacted. It was found that both cerium- and iron-doped titania have lower band-gap energy than pure titania and can be activated with visible light. The anatase and rutile phase transitions of these doped titania is however similar to pure titania and is unaffected by dopants. The crystalinity is however altered and crystal sizes in the range of six to nine nanometers were obtained with the sol−gel type synthesis of the titania catalyst. Although both cerium- and iron-based titania show destruction of these volatile organics in visible light as compared to pure titania, cerium-based titania has better performance than iron-based titania. A photocatalytic oxidation reaction pathway for linalool is proposed on the basis of previous studies and compounds are identified in the exit stream of the reactor. Further, reaction rate constants for toluene, linalool, ethanol, and acetaldheyhde have been determined using a two-dimensional diffusion model (Sidheswaran and Tavlarides, 2008), and are compared with values from literature. It has been found that cerium-doped titania developed in this study performs comparably to the commercially available titania even when irradiated with visible light. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900773m

Visible light photocatalytic oxidation of toluene using a cerium-doped titania catalyst / Meera Sidheswaran in Industrial & engineering chemistry research, Vol. 47 N°10 (Mai 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3346–3357 Titre : Visible light photocatalytic oxidation of toluene using a cerium-doped titania catalyst Type de document : texte imprimé Auteurs : Meera Sidheswaran, Auteur ; Lawrence L. Tavlarides, Auteur Année de publication : 2008 Article en page(s) : p. 3346–3357 Note générale : Bibliogr. p. 3356-3357 Langues : Anglais (eng) Mots-clés : Cerium-doped  titania  photocatalyst;  Toluene;  Mass  transfer Résumé : This paper focuses on the evaluation of the potential to use a cerium-doped titania photocatalyst activated by visible light to destroy volatile organics. Toluene is the model compound employed to test the photocatalyst, which is coated on the inner surface of an annular plug flow reactor. Mass transfer resistances are present and considered. Experiments were conducted over a range of residence times between 1 and 20 s and toluene concentrations between 150 and 600 ppb using constant visible-light intensity at room temperature. It is shown that the reaction kinetics can be approximated by a first-order expression with a reaction rate coefficient of 1.72 ± 0.015 s-1. The water adsorption coefficient was found to be 2.64 m3/mol. The catalyst also demonstrates mechanical and chemical stability during the course of the experiments conducted. These results indicate that the cerium based titania catalytic surfaces can be considered for application to destruction of volatile organic hydrocarbons in air using a visible light source. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie071276j [article] Visible light photocatalytic oxidation of toluene using a cerium-doped titania catalyst [texte imprimé] / Meera Sidheswaran, Auteur ; Lawrence L. Tavlarides, Auteur . - 2008 . - p. 3346–3357. Bibliogr. p. 3356-3357 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°10 (Mai 2008) . - p. 3346–3357 Mots-clés : Cerium-doped  titania  photocatalyst;  Toluene;  Mass  transfer Résumé : This paper focuses on the evaluation of the potential to use a cerium-doped titania photocatalyst activated by visible light to destroy volatile organics. Toluene is the model compound employed to test the photocatalyst, which is coated on the inner surface of an annular plug flow reactor. Mass transfer resistances are present and considered. Experiments were conducted over a range of residence times between 1 and 20 s and toluene concentrations between 150 and 600 ppb using constant visible-light intensity at room temperature. It is shown that the reaction kinetics can be approximated by a first-order expression with a reaction rate coefficient of 1.72 ± 0.015 s-1. The water adsorption coefficient was found to be 2.64 m3/mol. The catalyst also demonstrates mechanical and chemical stability during the course of the experiments conducted. These results indicate that the cerium based titania catalytic surfaces can be considered for application to destruction of volatile organic hydrocarbons in air using a visible light source. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie071276j