The idea first struck Oxford chemistry instructor Brenda Harmon as she was waiting to pick up her children from school. She noticed a funny smell coming from the car in front of her. Almost like French fries, she said, but French fries gone a little bad. The bumper sticker on the car read, "Ask me about biodiesel."
So when a discussion about service learning projects came up among the Oxford faculty, she suggested that her second-semester organic chemistry students, as their service project, could make biodiesel that could be used by the community.
Harmon applied for a $3,500 grant from Emory's Office of Sustainability Initiatives that allowed her to purchase a large biodiesel processor and electrical generator.
This semester, Harmon saw the idea finally become a reality as about 10 of her organic chemistry students took used cooking oil from the campus cafeteria and turned it into 40 gallons of industry-standard biodiesel.
"It's been so exciting! To know that this is biodiesel and it is pure," said Harmon, her face lighting up.
The process itself is not complicated, said Harmon. She points out anybody can make biodiesel, not just chemists.
The recipe they used essentially involves adding a catalyst, sodium methoxide, to filtered waste vegetable oil, which separates it into biodiesel and glycerine.
Draining away the glycerine and separating other impurities from the biodiesel, such as water and soapy residues, leaves biodiesel ready to use.
The class first made small batches in beakers and electric hot plates in the lab, based on a recipe from a popular biofuels Web site.
But taking that process and multiplying it into larger, usable quantities was a whole other ball game.
"I bit off a little more than I could chew, I think," said Harmon, who described struggling to lift a 250 pound barrel in and out of the lab and working the kinks out of testing a very noisy generator. "I've learned so much."
The first time she saw the oil and sodium methodxide mixture circulating through the boiler's tubes, she was so excited she hugged the barrel.
Though Harmon has been the driving force behind the project, her students have been just as interested and involved.
. Hong Tran, 20, a sophomore whose independent study project was making biodiesel, said at first it was intimidating. But ultimately, the experience helped her to decide that she wanted to major in chemistry.
The biodiesel will be used to run an inflatable bouncy house at Oxford College's Earth Day Celebration, but finding other uses for it has been a bit more difficult.
Even though the students tested the purity of their biodiesel to make sure it was up to industry standards, people are reluctant to use it in their cars, said Harmon.
"It's a new idea," she said. "It's going to take some time."
Emory's shuttle buses currently run on a B20 mixture, which means 20 percent of the diesel is biodiesel, but because of liability reasons, they haven't been able to incorporate the students' biodiesel into the supply.
Even though biodiesel is exciting, there are drawbacks, said Harmon. In many cases, having a fuel-efficient gasoline car may be a bigger energy savings than using biodiesel. And some of the ingredients in the recipe they used, such as methanol and sodium hydroxide (lye), need to be handled with care as they are caustic and flammable.
Still, Harmon plans to continue the biodiesel project with students in the coming semesters.
"What makes it nice is to see students excited about this and want to make a difference," she said. "That's hope for the future."
Web sites for more information:
Biodiesel locations: www.biodiesel.org/buyingbiodiesel/retailfuelingsites/
E85 Ethanol locations: www.e85refueling.com