RMIT University researchers have developed a water treatment material that rapidly removes micro and nano plastics and some PFAS, bringing the technology closer to real world use.
The invention, a dark adsorbent material that can be added to wastewater and separated with a magnet, builds on the team's 2022 breakthrough in microplastics removal, extending performance to much smaller particles and more complex wastewater.
Microplastics are an increasing global concern, with growing evidence of their presence in water systems.
The researchers say the ability to remove micro‑ and nano‑plastics under practical conditions sets this work apart.
Tests also showed removal of large molecules of PFAS compounds, which researchers say may be another promising application, though that part remains at an early stage.
First author Dr Muhammad Haris from RMIT's School of Engineering said the advance addressed a key gap in water treatment, which was the inability to remove nano-plastics at scale.
"Our material is designed to remove micro‑ and nano‑plastics quickly," he said.
Dr Muhammad Haris, Professor Nicky Eshtiaghi and Associate Professor Nasir Mahmood (left to right) display magnetic separation technology provided by their industry partner in Canada. Credit: Will Wright, RMIT University Putting removal to the test
In lab testing, the material removed more than 95 per cent of micro‑ and nano‑plastics, including particles as small as 30 nanometres, within one hour.
The material also removed more than 95 per cent of tested contaminants including mercury, chromium, copper, dyes and ibuprofen.
About 80 per cent were removed in the first 15 minutes, aligning with contact times used in treatment plants.
The material performed across common plastics such as polyethylene, polypropylene and polyester, and in both fresh and saline water.
From lab to wastewater
The team tested the material in industrial laundry wastewater, a major source of microplastic pollution from synthetic fibres.
It removed more than 88 per cent of polyester microfibres along with dyes, maintaining performance despite surfactants and organic matter.
A prototype system combining the adsorbent with magnetic separation technology from One Eye Industries in Canada showed the material could be recovered quickly after treatment and reused.
Co-lead researcher Associate Professor Nasir Mahmood from the School of Science said the results supported practical use.
"It worked in realistic water conditions, handled mixed pollutants and could be recovered efficiently," he said.
Roger Simonson, founder and inventor of One Eye Industries, said recovery of treatment material remained one of the biggest barriers to bringing new water treatment technologies out of the laboratory.
"Industry has been waiting for a practical way to move microplastics and emerging contaminants removal out of the laboratory and into real treatment environments," he said.
"The challenge isn't only capturing these particles, it's recovering the treatment material quickly and reliably after it has done its job, without creating a new waste stream.
"Combining high-performance pollutant capture with proven magnetic separation creates a much stronger pathway to real‑world deployment."
Professor Nicky Eshtiaghi holds a vial containing the team's magnetic adsorbent material designed to remove microplastics, nanoplastics and other contaminants from water. Credit: Will Wright, RMIT University Taking the technology to market
The team is working with Indigenous‑owned company Fire and Test Australasia, based in Geelong, Victoria, to explore the possibility of treatment of stormwater and wastewater, including in community settings.
Lead researcher Professor Nicky Eshtiaghi from the School of Engineering said the partnership reflected a shared focus on water stewardship.
"Cleaning and protecting water are deeply important for Indigenous communities as custodians of land and waterways," she said.
The researchers are also collaborating with Australian company Star Water Group, which has clients in the United States, including California, where tightening regulations are increasing demand for improved microplastics treatment.
Governments in Europe and the US are placing tighter limits on microplastics entering waterways, increasing pressure on industry.
Simonson said the technology showed strong potential for textile and industrial wastewater, municipal treatment systems, stormwater and decentralised water treatment.
"Professor Eshtiaghi and her team have brought deep scientific expertise and a clear grasp of the operational challenge, and we see real potential for this technology in textile and industrial wastewater, municipal treatment and other settings where microplastics and co-contaminants defeat conventional approaches," he said.
Close-up of the magnetic adsorbent material developed by Professor Nicky Eshtiaghi, Dr Muhammad Haris, Associate Professor Nasir Mahmood and colleagues for wastewater treatment applications. Credit: Will Wright, RMIT University A step change since 2022
Since 2022, the team expanded the material's capability, capturing particles from nanoscale plastics through to larger fibres while also removing dissolved contaminants in the same process.
Testing showed up to 90 per cent removal of mixed contaminants, with complete removal of fibres in textile wastewater.
Scaling up and improving affordability
Output increased fivefold through a room‑temperature manufacturing process using fewer costly inputs.
Early analysis suggested costs reduced by about 75 per cent compared to earlier versions. The material can also be reused multiple times, supporting cost‑effective use.
"Our goal was to make the technology effective, practical and affordable at scale," Eshtiaghi said.
"This includes ensuring the material can be recovered, reused and integrated into existing treatment systems."
