Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have polluted groundwater, rivers, lakes, and drinking water sources, impacting millions globally.
A team from Flinders University has introduced a novel technique to eliminate some of the most stubborn types of these durable contaminants from water.
Advanced Approach Focuses on Elusive PFAS Types
Under the guidance of Dr. Witold Bloch, an ARC Research Fellow at Flinders, the group engineered specialized absorbent materials that efficiently bind PFAS. This method excels at extracting short-chain PFAS, which conventional purification systems struggle to handle.
Their results, featured in Angewandte Chemie International Edition, describe a tiny molecular enclosure that functions as a precise trap for PFAS.
‘Although certain long-chain PFAS can be somewhat extracted with current methods, short-chain versions—which move easily through water—pose a significant ongoing problem,’ explains Dr. Bloch from Flinders University’s College of Science and Engineering.
‘We found that this small enclosure draws in short-chain PFAS by encouraging them to cluster inside its space. This robust attachment process differs from standard absorbents.’
Mechanism of the Molecular Enclosure System
To enhance performance, the scientists incorporated these enclosures into mesoporous silica, a substance that normally does not attract PFAS.
Lead author Caroline Andersson, a chemistry PhD student at Flinders University, notes that integrating the enclosure enables the material to extract various PFAS types from water, including the toughest ones.
‘The highlight of this work was our detailed examination of PFAS interactions within the enclosure at the molecular scale,’ she says. ‘This insight helped us grasp the exact attachment dynamics and apply it to build a strong absorbent for PFAS extraction.’
Strong Performance and Reuse Potential in Purification
Lab experiments revealed that the material eliminates up to 98% of PFAS at levels found in typical environments, using simulated tap water.
‘The absorbent proved reusable, maintaining strong results through at least five rounds. These outcomes suggest it could be added to water treatment setups for final-stage purification of drinking supplies,’ Dr. Bloch states.
‘This work marks a key advance in creating sophisticated materials to combat one of the planet’s most enduring environmental threats,’ he adds.
Rising Alarm About PFAS Contamination
PFAS are common in industrial processes, firefighting foams for aviation, and household items. They eventually seep into freshwater and ocean ecosystems, sparking worries over health dangers to people, animals, and ecosystems.
Funding and Resources: The research received support from Australian Research Council awards (FT240100330, DE240100664, DP230100587, CE230100021, FT220100054), Playford Trust PhD scholarships, and ATSE Elevate PhD scholarships. It utilized resources such as the MX1 and MX2 beamlines at the ANSTO Australian Synchrotron, an Australian Cancer Research Foundation detector, Flinders Analytical, Flinders Deepthought, the National Computational Infrastructure’s National Facility, and Microscopy Australia, supported by NCRIS and the South Australian government at Flinders Microscopy and Microanalysis.
