Researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) have discovered a method of plastics upcycling—that could economically incentivize the recycling of waste plastics and help solve one of the world’s most looming pollution problems.
Published in Joule, Combining reclaimed PET with bio-based monomers enables plastics upcycling describes how the NREL team chemically combined reclaimed polyethylene terephthalate (PET) plastic, in the form of single-use beverage bottles, with bio-based compounds to produce higher-value fiber-reinforced plastics (FRPs) that can be used in products from snowboards to vehicle parts to wind turbines. Upcycling, or transforming discarded products into new, high-value materials of better quality and environmental value, in other words. Not only are the resulting composites worth more than double the original PET, the FRPs exhibit twice the strength and improved adhesion to fiberglass when compared to the standard petroleum-derived FRP.
“Most recycling today is downcycling—there’s very little financial motivation,” said NREL Senior Research Fellow Gregg Beckham, one of the primary authors of the paper. “Knowing that 26 million tons of PET are produced each year but only 30% of PET bottles are recycled in the United States, our findings represent a significant advancement in enabling the circular materials economy.”
The NREL team also included staff polymer researcher Nic Rorrer, who has previously worked with bio-based muconic acid and breaking down reclaimed PET. “We are excited to have developed a technology that incentivizes the economics of plastics reclamation,” Rorrer said. “The ultimate goal is to reduce the amount of waste plastics in landfills and oceans.”
In addition, this process is more energy efficient and less hazardous than standard manufacturing processes for petroleum-based FRPs. NREL performed a supply-chain analysis of the FRP materials and found substantial energy savings and greenhouse gas emission reductions when compared to the process for producing petroleum-based composites. This research represents a potential step forward in sustainable methods to upcycle plastics into long-lasting, high-performance materials that could boost recycling efforts throughout the world.
The work reported in Joule was enabled by funding from NREL’s Laboratory Directed Research and Development program, with additional funding from the U.S. Department of Energy’s (DOE’s) Bioenergy Technologies Office.
Image: NREL Senior Research Fellow Gregg Beckham and Materials Scientist Nic Rorrer are working on a process of upcycling: breaking down PET in existing waste and combining it with compounds derived from biomass to make something more valuable, such as fiber-reinforced composite materials. Photo by Dennis Schroeder / NREL