Using Enzymes to Recycle Plastic

A more sustainable approach for recycling polyethylene terephthalate (PET) plastic used in single-use beverage bottles, clothing and food packaging, has been found by Bio-Optimized Technologies to keep Thermoplastics out of Landfills and the Environment (BOTTLE) consortium, which includes the U.S. Department of Energy National Renewable Energy Laboratory and the UK University of Portsmouth. A paper, “Techno-economic, life-cycle, and socioeconomic impact analysis of enzymatic recycling of poly(ethylene terephthalate),” in the journal Joule, shows that enzyme-recycled PET has potential advantages over conventional, fossil-based methods across a broad spectrum of energy and carbon impacts.

The concept could lead to new opportunities for PET recycling and create a mechanism for recycling textiles and other materials also made from PET that traditionally are not recycled. PET ranks among the most abundantly produced synthetic polymers in the world; roughly 54 percent is used in the manufacture of clothing and carpet. “From all the plastics that were produced since the 1950s, less than 10 percent of it has ever been recycled,” says Avantika Singh, first author of the paper. “Most waste plastics end up in landfills.” BOTTLE is addressing plastic pollution by developing energy-efficient, cost-effective and scalable recycling and upcycling technologies; and formulating modern plastics to be recyclable by design.