Point-of-use electrocatalytic filters for reduction of persistent contaminants from drinking water
Project Period:
2013
Project Investigator(s):
D. Cwiertny, D. Shuai, R. Valentine, Department of Civil and Environmental Engineering, The University of Iowa
Abstract:
Although regulated by the USEPA for the risk they pose to human health, nitrate and disinfection byproducts are pervasive contaminants often encountered in drinking water. Traditional approaches have proven inadequate for their removal; this project will develop a promising, point-of-use (POU) electrocatalytic filtration unit targeting these pollutants. With the potential for high pollutant removal efficiency and self-cleaning ability, this research will demonstrate the feasibility and sustainability of this technology. Specific tasks include synthesis and characterization of nanofiber supported metal catalysts exhibiting systematically varied physicochemical properties, assessing electrocatalytic filter performance when exposed to various water chemistries, and a preliminary environmental impact assessment addressing the cost and sustainability of this innovative technology. This work represents the first step in the development of a low-cost, POU water treatment device with the potential to lower health risks associated with drinking water sources compromised by persistent pollutant classes.
Project Results:
Drinking water supplies in Iowa are often contaminated with pollutants like nitrate and disinfection byproducts that adversely impact human health. Nitrate is a common problem in both public water systems and private drinking water wells, while disinfection byproducts are generated during water treatment with free chlorine and can also be produced during distribution via residual disinfectants. In both cases, an effective approach for limiting exposure to these pollutants is through treatment at the point of use (e.g., the tap). Here, we've produced nanotechnology enabled treatment devices that may one day help to limit the exposure of Iowans to these common contaminants in their drinking water supplies. Ongoing work is further refining this technology to improve performance and treatment efficiency.
There were three key results of this study.
- Developed novel catalytic materials for point of use water treatment.
- Used a process known as electrospinning to fabricate nanofibers decorated with noble metals used as hydrogenation catalysts. These materials, when treated with hydrogen gas, were able to reduce common drinking water pollutants including nitrate and disinfection byproducts.
- Follow-up work, since funded by NSF, is using this platform to produce innovative, electroactive materials for treatment of nitrate in waste brines from ion exchange systems. The researchers have also received NSF funding to fabricate novel piezoelectric materials, which transform mechanical energy (e.g., vibrations) into electrons that can be used for reduction reactions. When these piezoelectric materials are coupled with the noble metal catalysts, the researchers are able to produce a more sustainable approach for point of use water treatment.