Title: | Application of visible-light photocatalysis with nitrogen-doped or unmodified titanium dioxide for control of indoor-level volatile organic compounds |
Address: | "Department of Environmental Engineering, Kyungpook National University, Daegu 702-701, Republic of Korea. wkjo@knu.ac.kr" |
DOI: | 10.1016/j.jhazmat.2008.08.033 |
ISSN/ISBN: | 1873-3336 (Electronic) 0304-3894 (Linking) |
Abstract: | "The present study evaluated visible-light photocatalysis, applying an annular reactor coated with unmodified or nitrogen (N)-doped titanium dioxide (TiO(2)), to cleanse gaseous volatile organic compounds (VOCs) at indoor levels. The surface chemistry investigation of N-doped TiO(2) suggested that there was no significant residual of sulfate ions or urea species on the surface of the N-doped TiO(2). Under visible-light irradiation, the photocatalytic technique using N-doped TiO(2) was much superior to that for unmodified TiO(2) for the degradation of VOCs. Moreover, the degradation efficiency by a reactor coated with N-doped TiO(2) was well above 90% for four target compounds (ethyl benzene, o,m,p-xylenes), suggesting that this photocatalytic system can be effectively employed to cleanse these pollutants at indoor air quality (IAQ) levels. The degradation efficiency of all target compounds increased as the stream flow rate (SFR) decreased. For most target compounds, a reactor with a lower hydraulic diameter (HD) exhibited elevated degradation efficiency. The result on humidity effect suggested that the N-doped photocatalyst could be employed effectively to remove four target compounds (ethyl benzene, o,m,p-xylenes) under conditions of less humidified environments, including a typical indoor comfort range (50-60%). Consequently, it is suggested that with appropriate photocatalytic conditions, a visible-light-assisted N-doped photocatalytic system is clearly an important tool for improving IAQ" |
Keywords: | "Air Pollutants/*chemistry *Air Pollution, Indoor Catalysis Environmental Monitoring/*methods Humidity Light Nitrogen/*chemistry Photochemistry/*methods Titanium/*chemistry Volatile Organic Compounds/*chemistry Volatilization;" |
Notes: | "MedlineJo, Wan-Kuen Kim, Jong-Tae eng Research Support, Non-U.S. Gov't Netherlands 2008/09/24 J Hazard Mater. 2009 May 15; 164(1):360-6. doi: 10.1016/j.jhazmat.2008.08.033. Epub 2008 Aug 20" |