A Washington State University and University of Washington team has received a $2 million grant from National Science Foundation Emerging Frontiers in Research and Innovation (NSF EFRI) program for research to recycle and create valuable products out of municipal waste plastics.

The fundamental research aims to use catalytic processes to improve plastics recycling and to make it cost effective.

“This is a way to close the loop and to enable a circular economy,” said Hongfei Lin, associate professor in WSU’s Gene and Linda Voiland School of Chemical Engineering who is leading the project.

The accumulation of waste plastics has caused an environmental crisis, polluting oceans and pristine environments around the world. Varying types of plastics are used in a huge variety of products, from the polyethylene terephthalate (PET) in water bottles and polystyrene used in disposable coffee cups to polyethylene used in packaging films.

Because of the wide variety of chemicals and plastics used, recycling them often remains impractical. Recyclers most commonly sort the mix plastics first, melt them at high temperatures, and re‑mold them, resulting in poor-quality plastics with limited marketability.

Closeup of Hongfei Lin
Hongfei Lin

Chemical recycling can produce higher quality products, but it has required high reaction temperatures and a long processing time, making it too expensive and cumbersome for industries to adopt.

Because of its limitations, only about 9% of plastic in the U.S. is recycled every year.

As part of the new project, the researchers are developing an innovative waste plastics chemical upcycling process that will chemically rather than mechanically “sort” plastics in a step-by-step process, converting the co‑mingled waste plastics to monomers, which are the building blocks for plastics, and valuable chemicals.

“The novelty of this project is to integrate these processes and to develop highly efficient catalysts,” said Lin. “The process is designed to address the grand challenge in the plastic industry: how to deconstruct co‑mingled municipal waste plastics selectively. It sounds very straightforward, but there are a lot of technical challenges.”

The grant supports fundamental research. The UW researchers will be using computation tools and data science to assist design of catalysts and selection of solvents to improve the process efficiency. The researchers will also have access to high‑end facilities at Pacific Northwest National Laboratory (PNNL) to better understand reaction mechanisms.

Co‑principal investigators on the project include Yong Wang, Voiland Distinguished Professor in the Gene and Linda Voiland School of Chemical Engineering and Bioengineering, and Jim Pfaendtner from University of Washington, both of whom hold a joint appointment at PNNL.