Team Looks At Turning Plant Waste Into Plastic

Photo by James Runde.

A team at UW-Madison has a plan to turn plant waste into plastic. Some of the goals are to cut greenhouse gas emissions and create economic opportunities in rural Wisconsin.

The Wisconsin Energy Institute got $4 million from U.S. Department of Energy to turn a fibrous plant material called lignin into nylon. Nylon is in textiles, carpets and molded plastic. However, the project needs to make plant-based nylon for roughly the same cost as the petrochemical version but with only a fraction of the pollution. 

If successful, the project will demonstrate the commercial viability of a lab-tested process that could be key to developing sustainable alternatives to fossil fuels. This is according to Shannon Stahl, a UW-Madison professor of chemistry who is leading the project.

“If you’re really going to replace petroleum with bio-based feedstocks, everything from plants has to be turned into value,” Stahl says. “The approach must be like petrochemicals, where everything from crude oil is turned into something of value. The goal is to adapt the petrochemical model to a biochemical context.”

The process relies on a pair of innovations by UW–Madison researchers to separate individual molecules from complex chains found in plant fibers. Bacteria feed on those molecules and produce muconic acid. The acid converts into one of the two ingredients of nylon.
Image Credit: Matthew Wisniewski

But, the project aims to go beyond the engineering challenges. It incorporates a plan to collaborate with communities disproportionately affected by pollution and economic hardship.

Prof. Morgan Edwards will work with researchers to develop screening tools to guide the siting of biomass processing facilities. She says the goal is to ensure equitable distribution of both the benefits and burdens of energy infrastructure.

For example, Stahl says the sites could be located in communities in Wisconsin where paper mills have closed.

The grant is one of five. DOE’s Bioenergy Technologies Office awarded the grants as part of an initiative to advance the production of affordable biofuels and biochemicals that can reduce greenhouse gas emissions.