A magnetic material developed in Australia has eliminated more than 95% of microplastics and nanoplastics present in water samples. The tests also showed an effect on chemicals and some PFAS, a family of persistent products often called 'forever chemicals'.
The material is in the form of a dark adsorbent that traps contaminants. Once mixed with water, it can be recovered using a magnet. This property facilitates the separation of the material and captured particles after treatment.
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Researchers at RMIT University tested plastic particles, the smallest of which measured 30 nm. More than 95% of them were removed in one hour. About 80% of the removal occurred in the first fifteen minutes.
This speed is important for potential use in treatment plants. Water cannot generally stay indefinitely in a basin. A material that is effective in the first minutes could therefore better integrate into existing facilities.
The tests also covered other contaminants. The material removed a large part of mercury, chromium, copper, certain dyes, and even ibuprofen. These results show a broad action, but they do not guarantee the same effectiveness with all water qualities.
PFAS were studied separately. The material showed potential to remove some large molecules. This part of the work remains preliminary, as PFAS include thousands of compounds with different properties.
The tests were carried out in the laboratory, under conditions designed to approximate treatment plant waters. The lifespan of the material, its reuse, and the management of contaminants after capture remain to be evaluated.
The next step is to improve manufacturing and test the process on a larger scale. Industrial application will also depend on its cost, safety, and ability to operate with variable water volumes and qualities.