Promising University of Cincinnati student research turns coffee waste into biodiesel

In the long running quest to find alternative fuel sources, University of Cincinnati researchers are adding to the pursuit. They're in the early stages of scaling a process that converts coffee grounds into biodiesel.

Graduate student Yang Liu and doctoral student Qingshi Tu have been working on the project for nearly two years. Their research, which involves burning the grounds for energy after a purification process, was recently presented at the American Chemical Society's 246th National Meeting & Exposition in Indianapolis.

"We have three targets. First we extract oil from the coffee grounds, then we dry the waste coffee grounds in a process to filter impurities. Then we burn what's left as a source of energy generation (similar to using biomass)," explains Liu, an environmental engineering student.

The research is in the proof of concept stage, so it's proven promising in the lab, says Tu, also an environmental engineering student.

"Now we have to see how this will work on a large scale … in the next two years," he says.

The students are working with UC professor Mingming Lu on the process, which began in 2010. The project began small, starting with a five-gallon bucket of grounds from the campus Starbucks.

The project was one of four awarded a $500 UC Invents initiative grant last year. The grant supports campus innovators.

With the magnitude of coffee drinkers in just the U.S., the researchers have plenty of material to experiment with. It's estimated that one million tons of coffee waste is generated in the U.S. alone each year. Most of that sits in landfills.

By Feoshia H. Davis
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