Magnets key to removing dangerous PFAS chemicals


Queensland researchers have developed a way to quickly and simply remove dangerous PFAS chemicals from water using magnets.

Researchers from the University of Queensland have developed a method that does not require electricity or bulky lab equipment.

PFAS (perfluorinated and polyfluorinated alkyl substances) had been used extensively since the 1950s in a variety of forms, including in firefighting foam used at airports as well as in consumer products such as non-stick frying pans.

They are now believed to cause cancers and other illnesses, and are known as a “forever chemical” due to their tendency to remain in the environment without breaking down.

While they are no longer used, methods to remove them from local environments have been needed, especially where drinking water supplies have been contaminated.

Polymer chemist Dr Cheng Zhang and PhD candidate Xiao Tan at UQ’s Australian Institute for Bioengineering and Nanotechnology have spearheaded a way to quickly and easily remove the PFAS from water.

They use what is called a magnetic fluorinated polymer sorbent, which binds to the PFAS in the water.

“Because it has a magnetic element, we then simply remove the sorbent, and the PFAS along with it, using a simple magnet,” Zhang said.

The process is quicker than 30 seconds and removes over 95 per cent of the PFAS in the water sample.

Current methods for removing PFAS from water involve carbon filters and while they are also above 90 per cent effective, they can take up to 30 hours to remove the contamination and require bulky equipment, Zhang said.

The UQ developed method is also reusable up to 10 times.

Zhang said they were now working on scaling up the process from lab-based work to something that could be used in individual homes and on larger scales.

“We hope to have a commercially available product ready in the next three years,” he said. “Something you could buy from a supermarket in the same way that a lot of other water filtration products are available.”

The research received funding from the Australian Research Council, the National Health and Medical Research Council, The Chemours Company and the US Department of Defense.

Serious PFAS contamination has been recorded at a number of locations around Australia, including near defence bases at Oakey and Amberley in Queensland and Darwin and Katherine in the Northern Territory.

A number of lawsuits have been launched over the contamination, and the government is finalising a National Environmental Management Plan for PFAS.

The UQ research has been published in the journal Angewandte Chemie.

The Age, 20 January 2023