Vacuum Ultraviolet-Irradiated Photocatalysis: Advanced Process for Toluene Abatement
Publication: Journal of Environmental Engineering
Volume 137, Issue 11
Abstract
Photocatalysis with irradiation of a vacuum ultraviolet (VUV) lamp (VUV-PCO) was used to remove toluene in air. Two parallel reactions with irradiation of a 254 nm lamp (254 nm-PCO) and without (i.e., VUV photolysis) were conducted for comparison. The influencing factors of relative humidity, initial toluene concentration, and air flow rate were investigated. The results showed that VUV-PCO achieved much higher toluene removal efficiency and better PCO durability than 254 nm-PCO under different operating conditions. 82.3% toluene conversion was obtained with 1.8 ppm outlet concentration in the former, but only 14.5% with 30 ppm outlet concentration of was obtained in the latter under the conditions of 1% humidity, 50 ppm initial toluene concentration, and flow rate. Energetic photons from the VUV lamp could efficiently destruct toluene directly. formed from VUV irradiation of enhanced the toluene abatement by catalytic ozonation and inhibited the recombination of electron/hole pairs and deactivation of the photocatalyst. VUV-PCO could simultaneously overcome the limitations of the conventional PCO process. It is a promising technology for toluene abatement.
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Acknowledgments
The authors gratefully acknowledge the financial support from the conference and research grant of the University of Hong Kong (Grant No. UNSPECIFIED200907176159).
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Information
Published In
Journal of Environmental Engineering
Volume 137 • Issue 11 • November 2011
Pages: 996 - 1001
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Jul 20, 2010
Accepted: Apr 27, 2011
Published online: Apr 29, 2011
Published in print: Nov 1, 2011
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