A groundbreaking study from Northwestern University has developed a simple, environmentally friendly method to break down plastic waste using an inexpensive catalyst and air. The process, which harnesses trace amounts of moisture in the air, can convert polyethylene terephthalate (PET) into monomers – the building blocks for plastics.
The non-toxic, solvent-free approach uses a molybdenum catalyst and activated carbon to break apart PET bonds, followed by exposure to ambient air. This results in a highly selective process that recovers 94% of possible terephthalic acid (TPA) in just four hours.
This breakthrough technology offers a promising solution to the world’s plastic pollution problem. The US is the number one plastic polluter per capita, and only 5% of plastics are recycled. Current methods require harsh conditions, including high temperatures and expensive catalysts, generating toxic byproducts.
The Northwestern team has devised an elegant way to tackle plastic recycling issues without using solvents. Their approach uses water vapor from air, a readily available and sustainable resource that eliminates bulk solvents, reduces energy input, and avoids aggressive chemicals.
“We’re excited about our research because it harnesses moisture from air to break down plastics,” said Naveen Malik, the study’s first author. “This makes it not only environmentally friendly but also highly practical for real-world applications.”
The method works with mixed plastics, selectively recycling only polyesters, and can be used time and again without losing effectiveness. The researchers plan to optimize the process for large-scale industrial use to significantly reduce plastic pollution and contribute to a circular economy.
“The technology has the potential to make a tangible step toward a cleaner, greener future,” said Yosi Kratish, co-corresponding author of the study. “Innovative chemistry can address global challenges in a way that aligns with nature.”
Source: https://phys.org/news/2025-03-scientists-plastic-simple-inexpensive-catalyst.html