Performance of Silica-Titania Carbon Composites for Photocatalytic Degradation of Gray Water
Publication: Journal of Environmental Engineering
Volume 137, Issue 1
Abstract
The objective of this research was to develop a photocatalytic reactor that will reduce the total organic carbon (TOC) concentration of a gray water influent. The system used a reactor packed with titanium dioxide supported by silica gel and was optimized with respect to several system parameters. The composites (STCs) were capable of reducing the TOC concentration from 3,000 ppb to below the targeted concentration of 500 ppb in a recirculating system. An optimum empty bed contact time of 7 min was found based on the fastest destruction rate to reach below 500 ppb of TOC. Also based on destruction rate, a STC having a loading of 12 g/100 mL of precursor and approximately 120-Å pore size was shown to have the best performance among several composites of different loadings and pore sizes. The addition of activated carbon to the STC was found to improve the overall performance of the system by increasing the composite’s adsorption capabilities.
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Acknowledgments
The writers would like to thank the University of Florida–NASA Environmental Systems Commercial Space Technology Center for sponsoring this research.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 137 • Issue 1 • January 2011
Pages: 38 - 45
Copyright
© 2011 ASCE.
History
Received: Sep 29, 2009
Accepted: Jun 30, 2010
Published online: Jul 5, 2010
Published in print: Jan 2011
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