Researchers from the BOTTLE Consortium identified an enzyme that could create a sustainable approach to recycling polyethylene terephthalate (PET) plastics.

PET plastics are one of the biggest problems in relation to climate change and pollution. Enzyme-recycled PET production has many advantages over conventional fossil fuel-based PET production, including better energy, carbon and socioeconomic impacts. The new recycling method could be used for recycling textiles and other PET materials that are not currently recycled.Source: UnsplashSource: Unsplash

The BOTTLE Consortium set out to address plastic pollution and they identified two potential approaches. The first is to develop energy-efficient, cost-effective and scalable recycling and upcycling technology. The second approach is to design modern plastics to be recyclable by design.

In their paper, the team modeled a conceptual recycling facility that would take in a fraction of the three million metric tons of PET that is consumed annually. The enzymatic recycling process breaks down PET into two building blocks: terephthalic acid (TPA) and ethylene glycol.

The team determined that the enzymatic recycling process can reduce the total supply chain energy use by 69% to 83% and greenhouse gas emissions by 17% to 43%/kg of TPA. They also conducted an economy-wide comparison of virgin TPA and recycled TPA in the U.S. and proved that the environmental and socioeconomic effects of the two processes are not distributed equally across the supply chain. The proposed recycling process could reduce environmental impacts by up to 95% and generate up to 45% more socioeconomic benefits, like local jobs at material recovery benefits.

The team says there is potential for enzyme tech to decarbonized PET manufacturing and enable the recycling of waste PET-rich feedstocks and achieve cost parity with the traditional production of virgin PET.

The study was published in Joule.