NREL Says Don’t Recycle Single Use Plastics — Upcycle!

The National Renewable Energy Laboratory has been thinking a lot lately about single use plastics. Global warming and the Green New Deal are at the top of everybody’s agenda these days, but the Earth is drowning in discarded plastic. The oceans are inundated with millions of tons of plastic waste every year. Now that China has decided to stop accepting waste products from other countries, the pressure to find new solutions to our plastic waste problem has increased significantly.

Composite materials made from upcycled PET can be used in wind turbines, snowboards, or materials such as ballistic nylon and reusable bottles. Credit: Dennis Schroeder / NREL

The problem is really one of economics. There is no market for discarded single use plastic and so there is no economic model that permits entrepreneurs to recycle it and make a profit. It just gets thrown away in landfills or tossed into the sea. NREL researchers think they have a way of reusing certain types of discarded plastics profitably. Their plan is not to recycle it, but rather upcycle it. What does that mean?

It means using the discarded plastic as the raw material for new products that have economic value. The process applies to PETs, the common name for polyethelene terephthalate, used to make single use products like soda and water bottles because it is strong, lightweight, waterproof, and shatterproof. Without PET, the bottled water industry would not exist. But today, PET can only be recycled once or twice. NREL scientists want to change that.

“Standard PET recycling today is essentially ‘downcycling,'” Gregg Beckham, a senior research fellow at NREL. “The process we came up with is a way to ‘upcycle’ PET into long-lifetime, high-value composite materials like those that would be used in car parts, wind turbine blades, surfboards, or snowboards.”

The NREL researchers combined reclaimed PET with material derived from renewable sources such as waste plant biomass to create a new materials called fiber-reinforced plastics. FRPs have an economic value 2 to 3 times greater than the original PET. Not only that, the new products use 57% less energy than reclaiming PET using the current recycling process and emit 40% fewer greenhouse gases than FRPs derived from petroleum.

The findings of the NREL researchers were published February 27 in the journal Joule in an article entitled Combining Reclaimed PET with Bio-based Monomers Enables Plastics Upcycling. “The idea is to develop technologies that would incentivize the economics of PET reclamation,” says Beckham according to Science Daily. “That’s the real hope — to develop ‘second-life’ upcycling technologies that make single-use waste plastic valuable to reclaim. This, in turn, could help keep waste plastic out of the world’s oceans and out of landfills.”

We know getting new ideas out of the lab and into commercial production is often fraught with danger. The researchers are now busy assessing whether their ideas are scalable enough to support their use in manufacturing. They are also exploring similar technologies for recycling other types of materials.

“The scale of PET production dwarfs that of composites manufacturing, so we need many more upcycling solutions to truly make a global impact on plastics reclamation through technologies like the one proposed in the current study,” says first author Nicholas Rorrer, an engineer at NREL who also participated in the study.

So, is this big news? Not quite yet. But it certainly suggests important progress on an issue that directly impacts one of the most critical sustainability issues facing humanity.