Water filter designed to remove PFAS molecules

Monash University researchers have developed a water filtration membrane that effectively removes small PFAS molecules, overcoming a significant challenge faced by conventional water filters. Their work has been published in the journal ACS Nano.

Per- and polyfluoroalkyl substances (PFAS), commonly referred to as ‘forever chemicals’, are widely used in industrial and consumer products, persisting in the environment and posing potential health risks. PFAS contamination in Australia’s drinking water and waterways is a growing concern for communities, governments and water service providers. A federal inquiry is currently examining the scale of its use and impact nationwide.

The research team designed a beta-cyclodextrin modified graphene oxide (GO-βCD) membrane with nanoscale channels that selectively retain PFAS while allowing water to pass through. The membrane was fabricated using shear alignment printing, a scalable technique that allows for industrial-scale production of graphene oxide films.

In tests, the Monash membrane significantly outperformed traditional polyamide membranes, which typically remove only about 35% of short-chain PFAS. The team also confirmed that the membrane creates an energetic barrier that prevents PFAS passage — even under varying temperatures — while maintaining efficient water flow.

First author and Monash PhD candidate Eubert Mahofa highlighted the significance of this breakthrough in PFAS filtration.

“PFAS are difficult to manage because they dissolve easily in water and can spread far from their original source, making contamination challenging to contain and remediate. Removing small PFAS molecules from water has been a major hurdle for existing filters,” he said.

“Our approach solves this by filtering out and concentrating these harmful chemicals while still allowing water to flow through efficiently, making it a strong candidate to supplement the technologies for PFAS destruction.”

Dr Sally El Meragawi, co-researcher on the project, underscored the membrane’s potential impact on global water treatment strategies.

“By combining advanced materials with smart chemistry, we’ve created a highly efficient way to tackle this global contamination issue. The unique structure of our membrane enables it to effectively remove even the smallest PFAS molecules,” she said.

“Our approach also paves the way for future membrane technologies tailored for removing targeted contaminants in drinking and wastewater treatment applications. It also retains key nutrients in water, making it an attractive method for use alongside traditional nanofiltration systems.”

The work was supported by the ARC Research Hub for Advanced Manufacturing with 2D Materials (AM2D), whose director, Professor Mainak Majumder, emphasised the broader implications of the technology.

“This breakthrough in PFAS filtration has the potential to revolutionise how PFAS contamination is managed globally, with applications ranging from landfill leachate treatment to industrial wastewater purification,” Majumder said.

“Our technology opens new possibilities for developing advanced nanofiltration membranes tailored to remove specific molecular species by selecting appropriate binding chemistries.”

Clean TeQ Water and its graphene-focused subsidiary, NematiQ, are also supporting the development and commercialisation of the innovative membrane technology.

“The development of a modified graphene membrane for PFAS removal represents an exciting advancement in water treatment,” said Peter Voigt, CEO of Clean TeQ Water and NematiQ. “NematiQ looks forward to collaborating closely with Monash University to bring this innovative technology to market.”

Image credit: iStock.com/zimmytws