sunset on the water

October 05, 2020

SIU research team wins second round of funding for water pollution mitigation

by Tim Crosby

CARBONDALE, Ill. — Faculty and student researchers at Southern Illinois University Carbondale have secured a second round of funding from the U.S. Environmental Protection Agency to develop a process that uses light to remove a contaminant from water.

The EPA announced last week that SIU will receive $75,000 for Phase II funding from its “People, Prosperity and the Planet” grant program. The research team, led by Jia Liu, assistant professor of civil and environmental engineering, in 2018 received a Phase I grant from the “P3” program for the team’s work on the project titled “PFAS Removal by Photocatalysis for Water Re-use.” PFAS stands for pre- and polyfluoroalkyl substances. Such substances have made life easier in many ways, from being key ingredients in firefighting substances and waterproof, breathable fabrics to food packaging 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 EPA is taking special note of the issue, announcing drinking water health advisories when higher levels are detected and putting them on its list for further study.

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 received grants of up to $15,000 each to fund the proof of concept for their projects.

“Winning the Phase II funding creates the opportunity to convert our technology from bench-scale to pilot-scale, which is promising to lead to real applications of the PFAS degradation technology in wastewater effluents for reuse in irrigation,” Liu said. “In our Phase II study, for the first time, an innovative point-of-use system will be designed, manufactured and used.”

The SIU team includes faculty Boyd Goodson, Michael Lydy and Jane Geisler-Lee, as well as SIU students.

New technology tested

SIU’s project focuses on finding an elegant, low-cost way to remove the substances from wastewater effluent so that it can safely be reused for agricultural purposes. If successful, such a process could provide millions of gallons of water free of PFAS.

Photocatalysis is a process by which light is used to accelerate a chemical reaction. SIU’s team is using iron nanoparticles in photoreactors to remove PFAS from water samples. 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 involved bench-scale tests carried out in the laboratory. The researchers investigated removing PFASs first in deionized water using the iron nanoparticles with and without ultraviolet light. They then carried out the same experiment using wastewater effluents. They also looked at how the presence or absence of oxygen affects PFAS mitigation.

The Phase II system will include a sequencing batch photoreactor, using zero-valent iron nanoparticles and an ultraviolet C-radiation light, along with a magnetic chamber used to separate the used iron particles. The system will treat water both in the lab and at Northwest Wastewater Treatment Plant in Carbondale.

“We also will further study the impact of pH and dissolved oxygen concentration on PFAS removal in our Phase II study,” Liu said.