Quantcast

New Technology Uses Food Waste to Make Tires

Business

By Marlene Cimons

Some day you may discover tomato peels and eggshells where the rubber meets the road.

The environment—not to mention your tires—will be better for it.

Researchers at Ohio State University have discovered that food waste, specifically tomato peels and eggshells, makes excellent filler for rubber tires, with tests showing they exceed industrial standards for performance. Filler is combined with rubber to make the rubber composite used in tires. Food waste could partially replace carbon black, the petroleum-based filler long used in tire manufacturing, which has become increasingly hard to come by.

This approach to manufacturing more environmentally-friendly materials complements ongoing efforts to develop sources of clean fuel. Using tomato peels and egg shells as tire filler could help reduce the nation's dependence on foreign oil, keep food waste out of landfills and make the production of rubber items—especially tires—more sustainable, according to Katrina Cornish, who holds an endowed chair in biomaterials at Ohio State University.

"If we hit a real shortfall in carbon black, we'll have to use something else," Cornish said. "You could use some nice eggshells. Many companies would like to have a green position and this is a good way to do that."

Pixabay

Food accounts for around one-fifth of the waste sent to landfills, according to the U.S. Environmental Protection Agency. Finding ways to keep food waste out of landfills not only saves space, but also helps in the fight against climate change. Bacteria turn food and yard trimmings found in landfills into methane, a potent greenhouse gas.

When properly processed, food waste can be used to generate energy, enrich the soil as a fertilizer or serve as a food source for animals. Now, it also could prove valuable in tire manufacturing.

Cornish has long been interested in developing new sources of rubber, as well as ways to enhance rubber products. So, when she came to Ohio State in 2010, she looked to food waste as a potential tire filler.

"I wrote to every food processor in the state and said: 'if you've got waste, we'd like to look at it,'" she said. "We received 35 different types of waste: batter drippings, sauerkraut juice, milk dust powder, among them—and eggshells and tomato peels. I'd always wanted to look at tomato peels because I spent a lot of time in California and would see all those produce trucks loaded with tomatoes and knew they had to have thick, tough skins so the ones on top didn't squash the ones on the bottom."

Initially, Cornish had doubts as to how well eggshells would work. Eggshells are composed largely of calcium carbonate, which is used as an extender, rather than a reinforcer. The latter is more useful as tire filler. But Cornish discovered to her delight that her doubts were misplaced. Eggshells have a porous architecture that provides a larger surface area for contact with the rubber and proved to be reinforcing.

"We were very excited," she said. "It added considerably more value than expected." They also found that tomato peels are very stable at high temperatures and can generate material that performs well.

"Fillers generally make rubber stronger, but they also make it less flexible," said Cindy Barrera, a postdoctoral researcher in Cornish's lab. "We found that replacing carbon black with ground eggshells and tomato peels caused synergistic effects, for instance, enabling strong rubber to retain flexibility."

It also turned the rubber reddish brown—depending on the amount of eggshell or tomato in it—rather than the black appearance that results from using carbon black. About 30 percent of a typical automobile tire is made of carbon black, the cost of which varies with petroleum prices. American companies most often purchase carbon black from foreign sources, according to Cornish.

"The tire industry is growing very quickly and we don't just need more natural rubber. We need more filler too," Cornish said. "The number of tires being produced worldwide is going up all the time, so countries are using all the carbon black they can make. There's no longer a surplus…"

Particles of tomato peels and eggshells used by to make rubber composite. Katrina Cornish

Cornish and her colleagues' research on potential tire fillers has appeared in the Journal of Polymers and the Environment and elsewhere.

The U.S. produces around 80 billion eggs annually, according to the United Egg Producers. Cornish said that commercial food factories crack open half of them, then pay to send the remains to a landfill, where the mineral-loaded shells do not break down. "Nothing much happens to them in a landfill, since there are no calcium-eating animals," she said. "They are mostly rock."

The U.S. grows around 15 million tons of the ever-popular tomato, according to the Department of Agriculture. Most of that is canned or in processed products. When food companies make tomato sauce, for example, they peel and discard the skin, which is difficult to digest, she said.

Cornish is concerned about deforestation that results from planting new rubber trees and she has been researching rubber alternatives, including the rubber dandelion. While they are unmistakably dandelions, they are not the same as what many homeowners regard as annoying lawn and garden intruders.

Cornish explained that their leaves are thicker and bluer and the flowers are smaller. Most importantly, its taproot yields a milky fluid with natural rubber particles in it.

The rubber dandelion can be used to make tires. Biobased World

"The rubber dandelion comes from northwest China, Kazakhstan and Uzbekistan, but it can grow in snowy areas of Ohio," she said. "But it is not very sturdy, so we are trying to make it stronger and higher yielding." If successful, "it could grow as an annual crop and it could create many processing jobs," she added.

Meanwhile, Ohio State has licensed Cornish's technology for turning food waste into tire filler to her company, EnergyEne, for further development. Cornish stresses, however, that no one will start collecting "the eggshells from your breakfast," she said. "Kitchen waste is not going to go this way. So keep on with your compost piles. In fact, maybe you can use them to grow rubber dandelions."

Reposted with permission from our media associate Nexus Media.

EcoWatch Daily Newsletter

Tim P. Whitby / 21st Century Fox / Getty Images

The beauty products we put on our skin can have important consequences for our health. Just this March, the U.S. Food and Drug Administration (FDA) warned that some Claire's cosmetics had tested positive for asbestos. But the FDA could only issue a warning, not a recall, because current law does not empower the agency to do so.

Michelle Pfeiffer wants to change that.

The actress and Environmental Working Group (EWG) board member was spotted on Capitol Hill Thursday lobbying lawmakers on behalf of a bill that would increase oversight of the cosmetics industry, The Washington Post reported.

Read More Show Less
A protest march against the Line 3 pipeline in St. Paul, Minnesota on May 18, 2018. Fibonacci Blue / CC BY 2.0

By Collin Rees

We know that people power can stop dangerous fossil fuel projects like the proposed Line 3 tar sands oil pipeline in Minnesota, because we've proved it over and over again — and recently we've had two more big wins.

Read More Show Less
Sponsored
Scientists released a study showing that a million species are at risk for extinction, but it was largely ignored by the corporate news media. Danny Perez Photography / Flickr / CC

By Julia Conley

Scientists at the United Nations' intergovernmental body focusing on biodiversity sounded alarms earlier this month with its report on the looming potential extinction of one million species — but few heard their calls, according to a German newspaper report.

Read More Show Less
DoneGood

By Cullen Schwarz

Ethical shopping is a somewhat new phenomenon. We're far more familiar with the "tried and tested" methods of doing good, like donating our money or time.

Read More Show Less
Pixabay

Summer is fast approaching, which means it's time to stock up on sunscreen to ward off the harmful effects of sun exposure. Not all sunscreens are created equally, however.

Read More Show Less
Sponsored
Mark Wallheiser / Getty Images

The climate crisis is a major concern for American voters with nearly 40 percent reporting the issue will help determine how they cast their ballots in the upcoming 2020 presidential election, according to a report compiled by the Yale Program on Climate Change Communication.

Of more than 1,000 registered voters surveyed on global warming, climate and energy policies, as well as personal and collective action, 38 percent said that a candidate's position on climate change is "very important" when it comes to determining who will win their vote. Overall, democratic candidates are under more pressure to provide green solutions as part of their campaign promises with 64 percent of Democrat voters saying they prioritize the issue compared with just 34 percent of Independents and 12 percent of Republicans.

Read More Show Less
Flooding in Winfield, Missouri this month. Jonathan Rehg / Getty Images

President Donald Trump has agreed to sign a $19.1 billion disaster relief bill that will help Americans still recovering from the flooding, hurricanes and wildfires that have devastated parts of the country in the past two years. Senate Republicans said they struck a deal with the president to approve the measure, despite the fact that it did not include the funding he wanted for the U.S.-Mexican border, CNN reported.

"The U.S. Senate has just approved a 19 Billion Dollar Disaster Relief Bill, with my total approval. Great!" the president tweeted Thursday.

Read More Show Less
Reed Hoffmann / Getty Images

Violent tornadoes tore through Missouri Wednesday night, killing three and causing "extensive damage" to the state's capital of Jefferson City, The New York Times reported.

"There was a lot of devastation throughout the state," Governor Mike Parson said at a Thursday morning press conference, as NPR reported. "We were very fortunate last night that we didn't have more injuries than what we had, and we didn't have more fatalities across the state. But three is too many."

Read More Show Less