Technology rises, but not always without a potential cost. Take the case of so-called “PFASs.”
Such per- and polyfluoroalkyl substances have made life easier in many ways, from being key ingredients firefighting substances and waterproof, breathable fabrics to food packing and Teflon products.
But scientists also have noted these substances stick around in the environment long after being used. This, among other factors, gives PFASs the potential to build up in the bodies of living organisms, where they might potentially cause adverse effects. The U.S. EPA is taking special note of the issue, issuing drinking water health advisories when higher levels are detected and putting them on its list for further study.
SIU looks for answers
Researchers at Southern Illinois University Carbondale are among those on the vanguard of this effort, recently receiving a grant to fund a proof-of-concept study for mitigating PFAS. The EPA included a team led by Jia Liu, assistant professor in the civil and environmental engineering degree program, in its latest round of People, Prosperity and Planets – P3 – grants. The team also includes SIU researchers Michael Lydy, Boyd Goodson, and Jane Geisler-Lee, as well as SIU students.
The P3 competition challenges students to research, develop, and design innovative projects that address a myriad of environmental protection and public health issues. The Phase I teams will receive grants of up to $15,000 each to fund the proof of concept for their projects.
Team to test novel approach
SIU’s project, titled “PFAS Removal by Photocatalysis for Water Re-use,” will focus on finding an elegant, low-cost way to remove the substances from wastewater effluent so that it can safely be used for agricultural purposes. If successful, such a process could provide millions of gallons of water free of PFASs.
“With water shortages crisis in many regions in the U.S., water reuse has been proven a cost-effective solution, especially for agriculture, which can use around 70 percent of the freshwater in some areas,” Liu said.
Photocatalysis is a process by which light is used to accelerate a chemical reaction. SIU’s team will use iron nanoparticles in photoreactors to remove PFAS from water samples, Liu said. Using iron nanoparticles in this manner has never been tried, although such “zero valence” iron particles have been used for groundwater remediation in other scenarios. The researchers expect the process to work through the pathways introduced by the iron during photocatalysis.
The novel approach also will involve SIU students with diverse background in research. Students from the university’s REACH program, its undergraduate assistantship program, as well as the National Science Foundation’s Research Experiences for Undergraduates program will also participate.
Educational resources developed by the project also will be available for students in three Southern Illinois community colleges.
Researchers tackling common, worldwide problem
PFAS are commonly found throughout the environment, including in surface water, sediments, air, soil and sludge.
SIU’s Phase I project will involve bench-scale tests carried out in the laboratory. The researchers will investigate removing PFASs first in deionized water using the iron nanoparticles with and without ultraviolet light. They will then carry out the same experiment using wastewater effluent. They also will look at how the presence or absence of oxygen affects PFAS mitigation.
“The technology is superior to other technologies in its cost-effective and environment-friendly nature,” Liu said. “PFASs can be finally degraded and mineralized.” A magnet can be used to remove the iron nanoparticles from the water following the treatment, she added.
Many different talents required
The study requires an interdisciplinary team, including graduate and undergraduate student researchers from the civil and environmental engineering, zoology, chemistry and biochemistry, plant biology and finance degree programs. The nine student researchers are led by Chunjie Xia, a doctoral student in the civil and environmental engineering degree program.
Some students will collect wastewater effluent samples from Carbondale’s two wastewater treatment plants. Liu will supervise Xia and other students as they run the treatment experiments. Other students will examine the PFAS and water products post-removal, as well as the iron particles, while a finance student will run a cost-efficiency analysis of the process.
Success could bring further funding
The team this month attended the TechConnect World Innovation Conference and Expo in Boston to showcase its research. Liu plans to apply for a Phase II grant that provides funding up to $75,000 to further the project design.
Liu and her team hope that successful completion of their Phase I study will demonstrate the effectiveness of removing and reducing PFASs from the wastewater effluent. They hope to share such positive results with water treatment, water reuse, remediation, and agricultural communities through presentations at conferences and workshops, and publications in peer-reviewed journals.
“A sustainable method of removing and reducing PFASs from this water would reduce impact of PFASs on crops, on exposed soil and on surface water and groundwater for reuse in irrigation,” Liu said.