Quantcast
Environmental News for a Healthier Planet and Life

Researchers Find Energy Efficient Way to Convert Plastic Bags Into Diesel Fuel

Energy
Researchers Find Energy Efficient Way to Convert Plastic Bags Into Diesel Fuel

Plastic shopping bags, an abundant source of litter on land and at sea, can be converted into diesel, natural gas and other useful petroleum products, researchers report.

Used plastic shopping bags can be converted into petroleum products that serve a multitude of purposes. Graphic by Julie McMahon

The conversion produces significantly more energy than it requires and results in transportation fuels—diesel, for example—that can be blended with existing ultra-low-sulfur diesels and biodiesels. Other products, such as natural gas, naphtha (a solvent), gasoline, waxes and lubricating oils such as engine oil and hydraulic oil also can be obtained from shopping bags.

A report of the new study appears in the journal Fuel Processing Technology.

There are other advantages to the approach, which involves heating the bags in an oxygen-free chamber, a process called pyrolysis, said Brajendra Kumar Sharma, a senior research scientist at the Illinois Sustainable Technology Center (ISTC) who led the research. The ISTC is a division of the Prairie Research Institute at the University of Illinois. 

“You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil,” Sharma said. “But since this plastic is made from petroleum in the first place, we can recover almost 80 percent fuel from it through distillation.”

Americans throw away about 100 billion plastic shopping bags each year, according to the Worldwatch Institute. The U.S. Environmental Protection Agency (EPA) reports that only about 13 percent are recycled. The rest of the bags end up in landfills or escape to the wild, blowing across the landscape and entering waterways.

Plastic bags make up a sizeable portion of the plastic debris in giant ocean garbage patches that are killing wildlife and littering beaches. Plastic bags “have been detected as far north and south as the poles,” the researchers wrote.

Brajendra Kumar Sharma, center, a senior research scientist at the Illinois Sustainable Technology Center, with research chemist Dheeptha Murali, left, and process chemist Jennifer Deluhery, converted plastic shopping bags into diesel fuel. Photo credit: L. Brian Stauffer

“Over a period of time, this material starts breaking into tiny pieces, and is ingested along with plankton by aquatic animals,” Sharma said. Fish, birds, ocean mammals and other creatures have been found with a lot of plastic particles in their guts.

“Turtles, for example, think that the plastic grocery bags are jellyfish and they try to eat them,” Sharma said. Other creatures can become entangled in the bags.

Previous studies have used pyrolysis to convert plastic bags into crude oil. Sharma’s team took the research further, however, by fractionating the crude oil into different petroleum products and testing the diesel fractions to see if they complied with national standards for ultra-low-sulfur diesel and biodiesel fuels.

“A mixture of two distillate fractions, providing an equivalent of U.S. diesel #2, met all of the specifications” required of other diesel fuels in use today—after addition of an antioxidant, Sharma said.

“This diesel mixture had an equivalent energy content, a higher cetane number (a measure of the combustion quality of diesel requiring compression ignition) and better lubricity than ultra-low-sulfur diesel,” he said.

The team produced equivalents of (from left to right, in vials) gasoline, diesel #1, diesel #2 and vacuum gas oil. Photo credit: L. Brian Stauffer

The researchers were able to blend up to 30 percent of their plastic-derived diesel into regular diesel, “and found no compatibility problems with biodiesel,” Sharma said.

“It’s perfect,” he said. “We can just use it as a drop-in fuel in the ultra-low-sulfur diesel without the need for any changes.”

The research team also included Bryan Moser, Karl Vermillion and Kenneth Doll, of the USDA National Center for Agricultural Utilization Research, in Peoria, IL, and Nandakishore Rajagopalan, of the ISTC at the University of Illinois. 

The Illinois Hazardous Waste Research Fund and the Environmental Research and Education Foundation supported this study.

Visit EcoWatch’s ENERGY and BIODIVERSITY pages for more related news on this topic.

 

Matthew Micah Wright / The Image Bank / Getty Images

By Deborah Moore, Michael Simon and Darryl Knudsen

There's some good news amidst the grim global pandemic: At long last, the world's largest dam removal is finally happening.

Read More Show Less

EcoWatch Daily Newsletter

Scrap metal is loaded into a shredder at a metal recycling facility on July 17, 2008 in Chicago, Illinois. Scott Olson / Getty Images

Hunger strikers in Chicago are fighting the relocation of a metal shredding facility from a white North Side neighborhood to a predominantly Black and Latinx community on the Southeast Side already plagued by numerous polluting industries.

Read More Show Less

Trending

A new UK study links eating meat with increased risks for heart disease, diabetes and more. nata_zhekova / Getty Images

The World Health Organization has determined that red meat probably causes colorectal cancer in humans and that processed meat is carcinogenic to humans. But are there other health risks of meat consumption?

Read More Show Less
A common cuttlefish like this can pass the "marshmallow test." Hans Hillewaert / CC BY-SA 4.0

Cuttlefish, marine invertebrates related to squids and octopuses, can pass the so-called "marshmallow test," an experiment designed to test whether human children have the self-control to wait for a better reward.

Read More Show Less
Yogyakarta Bird Market, Central Java, Indonesia. Jorge Franganillo / CC BY 2.0

By John R. Platt

The straw-headed bulbul doesn't look like much.

It's less than a foot in length, with subdued brown-and-gold plumage, a black beak and beady red eyes. If you saw one sitting on a branch in front of you, you might not give it a second glance.

Read More Show Less