Researchers Create Biofuel out of Used Coffee Grounds

An estimated 1 million tons of coffee grounds are generated by java-loving Americans each year, and researchers at the University of Cincinnati have found a way to take what is usually thrown in a landfill and turn it into an alternative source of energy.

The early, but promising, discovery was presented this week at the American Chemical Society's 246th National Meeting & Exposition this week in Indianapolis.

By extracting the oils in the coffee grounds and drying out the remains, the researchers were able to convert the waste grounds into energy sources such as biodiesel and activated carbon.

"The researchers launched the project in 2010, gathering waste coffee grounds in a five-gallon bucket from a Starbucks store on UC's campus," the university said in a statement. "After collection, they removed the oil from the waste coffee grounds and converted triglycerides (oil) into biodiesel and the byproduct, glycerin. The coffee grounds were then dried and used to purify the biodiesel they derived from the waste coffee grounds."

Preliminary tests of the product showed that biodiesel fuel created by the waste grounds met the international D6751 standard.

"The efficiency of using the waste coffee grounds as a purification material to remove the impurities in crude biodiesel, such as methanol and residual glycerin, was slightly lower compared with commercial purification products," the university stated. "However, the researchers report that results still indicate a promising alternative, considering the cost of purification products. Future research will continue to focus on improving the purification efficiency of waste coffee grounds-derived activated carbon."

The biodiesel fuel created from the coffee grounds burns cleaner than traditional petroleum-derived fuel, emitting less carbon dioxide, hydrocarbons and particulate matter.

If future research into deriving biofuels out of coffee grounds proves successful and commercializable, it could be a boon to the biofuel industry, which faces criticism for using food crops such corn and soybeans for fuel sources.