By Scott Weybright, WSU College of Agricultural, Human, and Natural Resource Sciences

RICHLAND, Wash. – A research group led by Washington State University Tri-Cities scientists has found a way to turn daily plastic waste products into jet fuel.

In a new paper published in the journal , WSU’s Hanwu Lei and colleagues melted plastic waste at high temperature with activated carbon, a processed carbon with increased surface area, to produce jet fuel.

“Waste plastic is a huge problem worldwide,” said Lei, an associate professor in . “This is a very good, and relatively simple, way to recycle these plastics.”

How it works

In the experiment, Lei and colleagues tested low-density polyethylene and mixed a variety of waste plastic products, like water bottles, milk bottles, and plastic bags, and ground them down to around three millimeters, or about the size of a grain of rice.

The plastic granules were then placed on top of activated carbon in a tube reactor at a high temperature, ranging from 430 degree Celsius to 571 degrees Celsius. That’s 806 to 1,060 degrees Fahrenheit. The carbon is a catalyst, or a substance that speeds up a chemical reaction without being consumed by the reaction.

“Plastic is hard to break down,” Lei said. “You have to add a catalyst to help break the chemical bonds. There is a lot of hydrogen in plastics, which is a key component in fuel.”

Once the carbon catalyst has done its work, it can be separated out and re-used on the next batch of waste plastic conversion. The catalyst can also be regenerated after losing its activity.

After testing several different catalysts at different temperatures, the best result they had produced a mixture of 85 percent jet fuel and 15 percent diesel fuel.

Environmental impact

According to the , landfills in the U.S. received 26 million tons of plastic in 2015, the most recent year statistics are available. China has recently stopped accepting plastic recycling from the U.S. and Canada. Conservative estimates by scientists say that at least 4.8 million tons of plastic enters the ocean each year worldwide.

Not only would this new process reduce that waste, very little of what is produced is wasted.

“We can recover almost 100 percent of the energy from the plastic we tested,” Lei said. “The fuel is very good quality, and the byproduct gasses produced are high quality and useful as well.”

He also said the method for this process is easily scalable. It could work at a large facility or even on farms, where farmers could turn plastic waste into diesel.

“You have to separate the resulting product to get jet fuel,” Lei said. “If you don’t separate it, then it’s all diesel fuel.”

This work was funded by the Agriculture and Food Research Initiative Competitive Grant no. 2014-38502-22598, 2016-67021-24533, 2018-67009-27904 from the , .

Washington State University Tri-Cities is the home of the Bioproducts, Sciences and Engineering Laboratory, a state-of-the-art research facility operated in partnership with the Pacific Northwest National Laboratory. The facility establishes the Tri-Cities as a center for world-class bio-based product research and development.

By Maegan Murray, ���سԹ�

RICHLAND, Wash. – ���سԹ� associate professor Xiao Zhang is targeting the use of lignin — a common material that makes the cell walls of plants rigid — to create affordable biofuels and bioproducts.

Interested in the project, the U.S. Department of Agriculture’s National Institute of Food and Agriculture has granted , an associate professor in WSU’s Bioproducts, Sciences and Engineering Laboratory, $500,000 to complete the research. The laboratory is part of the university’s .

The project will be conducted in partnership with Xuejun Pan, a professor in the department of biological systems engineering from the University of Wisconsin-Madison.

Lignin is one of the largest renewable carbon sources on Earth. It allows trees to stand, gives vegetables their firmness and makes up about 20-35 percent of the weight of wood. It also is one of the largest remnant products left over in the biofuels creation process.

Zhang and his team will investigate new conversion pathways to produce chemicals and biofuels without completely breaking down lignin into monomers — molecules that can be synthesized into polymers. In addition to its potential cost savings, the process could maximize carbon utilization in the biofuels creation process. It would also provide a profitable use for a waste product.

“We aim at converting lignin into a skeleton that has a similar carbon length in jet fuel range,” Zhang said. “The uniqueness is really targeting a more cost-effective process in taking advantage of the basic lignin structure of characteristics. Unlike many other processes, we don’t have to break down the lignin completely to its monomers.”

Contacts:

• Xiao Zhang, WSU Bioproducts, Sciences and Engineering Laboratory associate professor of the Voiland School of Chemical Engineering and Bioengineering, 509-372-7647, zhang@wsu.edu

RICHLAND, Wash. – Researchers at Washington State University Tri-Cities have been awarded a National Science Foundation I-Corps grant to explore the market potential of their biojet fuel research.

Bin Yang, associate professor of biological systems engineering and principal investigator for the grant, and his team have spent several years developing a process for transforming lignin, a polymer that makes plants woody and rigid, and currently a waste product in the biofuels production process, into hydrocarbon molecules that can one-day be certified as jet fuel.

Yang said by leveraging research results from projects funded by the Defense Advanced Research Project Agency, the National Science Foundation, the Department of Energy, the Department of Transportation, the Joint Center for Aerospace Technology Innovation and The Boeing Company, he and his team have successfully demonstrated a new, water-based process for deconstructing and recovering lignin from biomass and converting it into jet fuel-range hydrocarbons that may be certified as jet fuel in the near future. Yang currently holds a patent on the process.

“Our ultimate goal is to demonstrate a flexible catalytic process that selectively converts all the carbon in the lignin into jet fuel-range hydrocarbons at minimal cost,” he said.

Libing Zhang, a ���سԹ� postdoctoral research associate and the entrepreneurial lead of the project, said currently commercial airlines are facing pressure to reduce emissions, which is why they may have an interest in seeing a lignin-derived alternative fuel brought to market.

“The airlines see alternative jet fuel as a strategic need, helping guarantee smooth business operations and a long-term and sustainable jet fuel supply,” Zhang said. “Our conversion process can potentially reduce jet fuel cost to end users by using lignin waste from refineries and less expensive catalytic upgrading to jet fuel.”

Zhang said the NSF I-Corps program helps leading researchers develop a business platform for their research and technology that could one-day change the world, while not trying to “reinvent the wheel” by recreating processes and strategies that are already working well within the industry.

For the NSF I-Corps grant, Yang and his team are working under the mentorship of Terri L. Butler from the University of Washington for the business aspects of the project.

“The NSF I-Corps program encourages researchers to step out of the academic environment and listen to the needs of industry,” Butler said. “The researchers can then determine if their technology solves an important problem or if their research efforts should head in a different direction. This is the approach our team has taken as we work on possible business models for our biojet fuel technology while considering the needs of customer segments, key partners, cost structures and revenue streams.”

WSU is leading the nation in biofuel production. In November, Alaska Airlines made the first commercial flight using alternative jet fuel from forest residuals produced through WSU-led Northwest Advanced Renewables Alliance. Read more .

WSU also has an NSF I-Corps site led by the Voiland College of Engineering and Architecture that provides training and funding to find commercial applications of new business ideas and technologies. The free site program promotes entrepreneurism of faculty, student and staff by preparing participants for submission of a proposal to NSF to become an I-Corps team. Learn more .

 

News media contacts:
Bin Yang, ���سԹ� biological systems engineering, 509-372-7640, binyang@tricity.wsu.edu
Libing Zhang, ���سԹ� postdoctoral research associate, libing.zhang@wsu.edu
Maegan Murray, ���سԹ� public relations, 509-372-7333, maegan.murray@tricity.wsu.edu