Breakthrough PFAS Removal Technology Offers Hope for Water and Wastewater Treatment
November 14, 2024 — Researchers at the University of Illinois Urbana-Champaign have introduced a revolutionary device capable of capturing, concentrating, and destroying a wide range of per- and polyfluoroalkyl substances (PFAS) in contaminated water—all in a single step. This breakthrough could have significant implications for industries struggling with PFAS contamination, particularly the rapidly expanding semiconductor sector.
The device, which uses a combined approach of redox electrodialysis and electrosorption, addresses the challenges of capturing PFAS chemicals of varying molecular lengths, including ultra-short-chain PFAS, which are particularly hard to remove due to their small size and unique chemical behavior.
Innovative Use of Redox Electrodialysis
Lead researcher Professor Xiao Su, of Illinois’ chemical and biomolecular engineering department, explained that they selected redox electrodialysis for its effectiveness with ultra-short-chain PFAS, which act like salt ions in water. By coupling redox electrodialysis with electrosorption, the device can target and capture all PFAS molecules, concentrating them for easier destruction through electrochemical oxidation.
A previous study by Su’s team showed that electrosorption could remove short- and long-chain PFAS but struggled with the ultra-short-chain variants. The new system overcomes this by combining electrodialysis with a specialized, cost-effective nanofiltration membrane, which captures PFAS molecules without becoming fouled.
Optimizing for Efficiency and Cost
The team’s configuration places a carbon electrode alongside a nanofiltration membrane, creating an efficient device that can simultaneously desalt the contaminated water, capture the entire PFAS size spectrum, and concentrate them for destruction. The electrochemical oxidation step converts the PFAS molecules into fluoride ions, ultimately removing them from the water supply.
Su emphasized the relevance of this technology given the high demand for PFAS removal solutions from industries like semiconductors, where PFAS-free production is becoming increasingly important. “This work is very timely due to interest from the U.S. government, wastewater treatment facilities, and the semiconductor industry,” Su said, noting that the device is being prepared for field applications in wastewater treatment facilities.
Supporting Sustainable Manufacturing
As semiconductor manufacturing is projected to grow, sustainable PFAS abatement will be crucial. This new device could be incorporated into industrial wastewater treatment systems, offering a practical solution to tackle PFAS contamination at its source.
The study, “Integrating redox-electrodialysis and electrosorption for the removal of ultra-short- to long-chain PFAS,” was published in Nature Communications and supported by the National Science Foundation ERASE-PFAS program. Researchers Nayeong Kim, Johannes Elbert, and Ekaterina Shchukina contributed to the project, marking a critical advancement in environmental technology for cleaner and safer water.
