A five-year effort to develop a lower-cost source of biodiesel has led Wake Forest University chemists in the direction of a sugar-based compound to accomplish their goal.
Biodiesel is a renewable, clean-burning fuel that also reduces tailpipe emissions. It depends primarily on feedstock crops.
The researchers' work will appear in an edition of the journal Bioresource Technology.
Analysts say there has been plenty of competition and methodologies for producing a lower-cost catalyst for biodiesel, but little sustainable, cost-effective success.
The most commonly used raw material for biodiesel is soybean oil. But its high cost has stifled major production efforts. Also, low-quality oils contain a high percent of free fatty acids that can impede biodiesel production.
Wake Forest's Terrafinity project doesn't depend on soybean oil. It currently relies on a method that, like making sausage, may produce results but is not for the squeamish.
The Wake project uses vegetable-oil waste, animal-fat waste, recycled cooking grease and even oils extracted from municipal sewage- and water-treatment plants. Other scientists are exploring algae as a source. The researchers get some of the raw materials for free, and for now pay a nominal price for other supplies.
"Right now, you and I actually pay companies to come and dispose of sewer and used oil waste," says Abdou Lachgar, a chemistry professor at Wake Forest and the project's lead researcher.
"What we want to do is to take the fat out of that waste and convert it to energy."
Now the researchers are looking at a process that would reduce the cost of making biodiesel.
The sugar-based compound being developed by Wake Forest and Virginia Tech researchers would serve as an alternative to sulfuric acid, a highly corrosive liquid that erodes production equipment and harms the environment. Free fatty acids have to be converted to biodiesel separately through a process called esterification, which requires sulfuric acid.
By comparison, the sugar-based compound is inexpensive, environmentally friendly and easy to filter out from produced biodiesel.
"Unlike liquid sulfuric acid, which has to be neutralized over a long period of time, our catalyst is a solid and can be separated relatively easily," Virginia Tech chemist Brian Hanson said.
A feasibility study by Wake Forest Schools of Business found that the catalyst could reduce costs by as much as 15 percent for a small-scale biodiesel production facility. The cost-reduction impact on larger-scale facilities requires more research, Lachgar said.
Dan Fogel, an executive professor of strategy at Wake Forest Schools of Business, said the lower-cost biodiesel production makes commercial sense in providing an energy source for the developing world or on an island.
"In these kinds of places, energy costs can be as much as 50 cents a kilowatt hour," Fogel said. "In Winston-Salem, you pay around 11 or 12 cents per kilowatt hour.
Biodiesel is not likely to replace gasoline as the main source of transportation fuel in most of our lifetimes.
But Wake Forest researchers say their catalyst could help lower the cost of producing biodiesel enough so that it could provide 5 percent of the nation's needs.
"If we, as a nation, can do that, that's enough biodiesel to replace the need for oil from a country such as Iraq," Lachgar said.
The research was funded by the Biofuels Center of N.C.
That funding source will end on Oct. 31 because of the General Assembly's decision to eliminate its $2.06 million funding from the 2013-15 state budget. It also received $2.24 million from Tennessee Valley Authority Settlement Funds. A private nonprofit corporation, the center had been considered among the nation's top models for comprehensive biofuels development.
One of the center's goals had been developing a statewide industry that would produce at least 10 percent of the liquid fuels sold in the state by 2017.
One roadblock is that there are few retail outlets for biodiesel in North Carolina. There are six in the Triad, including two each in High Point and Lexington, and one each in Burlington, Colfax and Greensboro.
