Grad student shows junior high class how to make bio-diesel
The students at Skyview School are too young to drive, but they know how to make bio-fuel.
Prescott College graduate student Michael Freeman gave Skyview School students a crash course on making bio-diesel on Monday.
Freeman, whose graduate thesis expounds on the sustainability of bio-fuel and its potential, explained to the seventh- and eight-graders the basic chemistry of bio-diesel and let them experiment on their own with its composition.
Freeman led teams of three to four students each through experiments illustrating the home-brewing simplicity of making the fuel, using in this instance used vegetable oil.
"You can generally find the waste stuff for free," said Freeman, who claims to fuel his diesel sedan with used vegetable oil from area restaurants.
Freeman's experiment was part of illustrating how vegetable oil and methanol becomes bio-diesel.
After explaining the chemical structure of tryglycerides, in this case vegetable oil, and the chain of reaction converting it to bio-fuel, Freeman let the students conduct their own titration tests and find the right amount of a catalyst needed to neutralize free fatty acids in the oil.
Diesel engines can process pure vegetable oil; however, vegetable oil without free fatty acids, or glycerin, with methanol actually produces bio-diesel, which burns cleaner than pure vegetable oil.
Once students determined the quantity of the catalyst they needed, Freeman drew up a recipe for a batch of bio-diesel made up of one liter of vegetable oil, 200 ml of methanol, and five grams of lye.
Freeman explained that the mix requires heating the vegetable oil to about 130 degrees.
"If you're planning on taking this up as a hobby, I suggest consulting your parents, doing some research online, and finding a good home-brewing guide," Freeman said after pointing out the benefits of bio-diesel, as well as the arguments against it.
Students asked questions like what kind of mileage it produces, what kind of engine people need, "how fast can you go," and "does it work in a Hummer?"
"It's really nice to have a second source of fuel," said eighth-grader Sade Pritchett.
Seventh-grader Remi Spooner said he was eager to try making his own fuel.
"I already knew about this. I just didn't know how to make it," he said.