Word (http://tools.niehs.nih.gov/portfolio/sc/detail_doc.cfm?appl_id=7285322&ext=.doc)
|
Excel (http://tools.niehs.nih.gov/portfolio/sc/detail_xls.cfm?appl_id=7285322&ext=.xls)
|
PDF (http://tools.niehs.nih.gov/portfolio/sc/detail_doc.cfm?appl_id=7285322&pdf=1&ext=.pdf)
A Novel Nanocomposite Photocatalyst for Water Treatment
Principal Investigator
Gonzalez-Martin, Anuncia
Institute Receiving Award
Lynntech,, Inc.
Location
College Station, TX
Grant Number
R44ES012517
Funding Organization
National Institute of Environmental Health Sciences
Award Funding Period
15 Sep 2003to30 Apr 2009
DESCRIPTION (provided by applicant): The availability of safe drinking water is a substantial health concern. The introduction of water chlorination as a standard water treatment has resulted in a significant decrease in the number of waterborne diseases. However disinfection byproducts (DBPs) are formed by the reactions between chlorine and the natural organic matter (NOM) dissolved in water. Long-term exposure to DBPs may increase the risk of cancer and other adverse health effect. As a consequence, the U.S. Environmental Protection Agency (EPA) has implemented stringent limits for DBPs in drinking water. Although the use of alternative disinfectants have been proposed, they also produce their own toxic byproducts. And water plant approaches to reduce the amount of NOM in the source water prior to chlorination step are not technically sound due to the requirement of a new water treatment plant that is costly to construct and operate. Thus, new methods for elimination of DBPs in drinking water at the point-of-use (POU) are strongly needed.
The objective of the Phase II proposal is to design, fabricate and test a new, small-scale photocatalytic oxidation system for POU water treatment. The aim is to provide a unique, low-cost consumer device designed to effectively eliminate DBPs and microorganisms at the location where water is consumed. The proposed system provides attractive benefits over other POU technologies because it adds nothing harmful to the water, does not require routine service, does not provide a harbor for microorganism growth, and water contaminants including DBPs and microorganisms are destroyed, not just transferred from water to solid phase, and therefore, it does not create a waste disposal problem.
During the Phase I project, Lynntech developed and successfully tested bench scale photocatalytic systems capable of fast degradation of a variety of microorganisms and DBPs to well bellow EPA recommended levels. It overcame limitations of other photocatalytic system including deactivation by inorganic ions. The heart of Lynntech's water treatment is the use of effective photocatalyst nanoparticles immobilized on an active matrix. The photocatalyst material is integrated into an ingenious reactor design that minimizes mass transfer and allows for fast treatment times. During the Phase II, an optimized automated GEN I POU photocatalytic water treatment will be developed. We will test it for its reliability, repeatability, ease of use, manufacturability and ease of assembly while minimizing its cost. Its operation will be on-line, and user interaction will be limited to the replacement of the UV lamps after about 5,000 hours of use. GEN I POU system will be extensively tested with DBPs and microorganisms commonly found in tap water.
The proposed system has a high potential for user acceptance and has immediate commercial applications in many areas where high quality water is needed. Key segments where the proposed technology can have an immediate impact include hospital, schools, pharmacies, cafeteria, commercial and residential buildings, etc.
The availability of safe drinking water is a substantial health concern. The introduction of water chlorination as a standard water treatment has resulted in a significant decrease in the number of waterborne diseases, but disinfection byproducts (DBPs) are formed by the reactions between chlorine and the natural organic matter (NOM) dissolved in water, and long-term exposure to DBPs may increase the risk of cancer and other adverse health effect. The aim of this Phase II proposal is to provide a unique, low-cost, small-scale photocatalytic oxidation system for point-of-use water treatment device designed to effectively eliminate DBPs and microorganisms at the location where water is consumed.
Crisp Terms/Key Words: nanotechnology, nonbiomedical equipment, technology /technique development, water treatment, water sampling /testing, microorganism toxicology, photochemistry, oxidation, catalyst
|