Scientists have developed a new catalyst system that can break down per-and poly-fluoroalkyl substances more efficiently than previous methods.
PFAS, a so-called "forever chemical", was the primary ingredient in fire fighting foam used at defence bases, including RAAF Base Williamtown, for decades.
The Department of Defence has to date spent more than $100 million in recent years remediating PFAS hotspots using traditional technologies to break down the chemical.
The new method of degrading PFAS was developed by Dr Jun Sun and Professor Naresh Kumar from UNSW's School of Chemistry, who worked alongside Professor Denis O'Carroll, Professor Michael Manefield and Dr Matthew Lee from the UNSW School of Civil and Environmental Engineering.
Dr Sun said there was an ongoing need to come up with an energy-efficient and environmentally friendly way to remove PFAS from water.
Since the chemical can take about 1000 years to break down, even if it was removed from water sources, there is still an issue about how to dispose of it.
"You could bury it in the ground, but it'll still end up in your groundwater supply which is where the problem started in the first place," UNSW water expert Professor Stuart Khan said.
Previous research has shown nano zero-valent metals and vitamin B12 can be used to degrade PFAS.
Professor Kumar and Dr Sun tested their method by mixing the PFAS chemicals with nZVMs and the porphyrin ring (organic chemicals) in a buffer solution and measured the breakdown of the PFAS.
"We did this by following how much fluoride is released as those strong carbon-fluoride bonds are broken down," Dr Sun said.
"So, by simply measuring the amount of fluoride ion that is produced by the reaction, we can tell how much of the PFAS have been degraded."
The results revealed about 75 per cent of the fluoride had been released from branched PFOS and PFOA within five hours.
The B12 based catalyst system only showed less than 8 per cent defluorination within five hours.
The next step is to scale up the project and test it in a water purification system or at sites that are contaminated with PFAS.
"As modern consumers, if we really want to limit our use of PFAS, we need to do our research and look into what products are made from - because there is PFAS in a lot of things that you wouldn't even consider," Professor O'Carroll said.
Residents of Williamtown, Oakey and Katherine settled a $132.7 million class action with the federal government in 2020 for the loss of value to their land resulting from PFAS contamination.
A March 2023 groundwater analysis of PFAS contamination around the Williamtown RAAF based indicated the contamination plume is moving away from the base in a southerly direction.
Many landowners in the area are eagerly awaiting the federal government's response to a series of recommendations from Jim Varghese AM, who examined alternative options for PFAS contaminated land around RAAF Base Williamtown, the Army Aviation Centre Oakey (QLD), and RAAF Base Tindal (NT).
