Australian scientists have found a fast and simple method to break down 90% of plastic waste in just 30 minutes. The process uses air, purple LED light, and a small amount of common iron salt – without the need for expensive or rare materials – reported Earth.com.
The research was led by Dr Maxime Michelas from the University of New South Wales. The team discovered that when iron(III) chloride is exposed to purple light, it creates chlorine radicals. These radicals break the plastic’s chemical bonds, and oxygen from the air finishes the job. The plastic quickly breaks down into smaller parts that can be used to make paints, adhesives, and fragrances.
Tests showed that this method worked on seven common types of plastic, including hard-to-break-down materials like PVC. After just 30 minutes, most plastics lost 90% of their mass. If the process runs for three hours, up to 97% can be broken down.
Unlike other methods such as pyrolysis – which requires high temperatures and a lot of energy – this process runs at room temperature and uses very little electricity. For example, a small 15-watt LED light running for half an hour uses only 0.015 kWh. That’s far less than the 1,550 kWh needed to treat a tonne of plastic using pyrolysis.
This approach could be useful for breaking down foam polystyrene, which takes up a lot of space in landfills even though it weighs very little. Waste centres could use this method to melt plastic on-site, saving money on transport and storage.
Although this solution won’t clean up the microplastics already in our environment, it could stop new ones from forming – especially from takeaway containers and other single-use plastics.
The research team hopes to test the method on more types of plastic and explore ways to use sunlight instead of LEDs. With further development, this Australian innovation could make plastic recycling cheaper, cleaner, and more effective.