New Catalytic Process Offers Efficient Recycling for Polyester Plastics

Published in Cell Reports Physical Science, the research introduces an inexpensive catalytic sorting technique that fully deconstructs polyester into its monomers—dimethyl terephthalate and ethylene glycol—even from complex plastic mixtures. This breakthrough could facilitate the recycling of polyester to produce new, high-quality plastics comparable to first-generation materials.

Professor Hongfei Lin, the study's corresponding author, highlighted the catalyst's efficiency and the mild operating conditions required. "We achieved very high yields under mild conditions," Lin said, noting that this development could make plastic recycling more viable on a larger scale.

Traditional polyester recycling methods are costly and inefficient, often resulting in lower-quality recycled plastics. Chemical recycling, while promising, has required high temperatures and long processing times. The new method addresses these challenges by using methanol and a cost-effective catalyst to break down polyethylene terephthalate (PET) at 160°C (320°F) in just an hour. The process also works on mixed plastics and multi-layer plastic films like vacuum-sealed bags, which are typically difficult to recycle.

"This technology enables the recovery of high-quality materials from mixed plastic waste," Lin said, emphasizing its potential to tackle multi-layer plastic films, a major industry challenge.

Supported by the National Science Foundation, this research, conducted in collaboration with Pacific Northwest National Laboratory and the University of Washington, paves the way for more efficient and cost-effective plastic recycling, helping reduce waste and its environmental impact.

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November 15, 2024 | Voiland College of Engineering and Architecture| New method holds potential to efficiently recycle widely used polyester plastics