Anyone who's overheated vegetable oil or sweet syrup knows that neither oil nor sugar evaporates--oil smokes and turns brown, sugar turns black, and both leave a nasty film of carbon on the cookware. Now, a University of Minnesota team has invented a "reactive flash volatilization process" that heats oil and sugar about a million times faster than you can in your kitchen and produces hydrogen and carbon monoxide, a mixture called synthesis gas, or syngas, because it is used to make chemicals and fuels, including gasoline. The new process works 10 to 100 times faster than current technology, with no input of fossil fuels and in reactors at least 10 times smaller than current models. The work could significantly improve the efficiency of fuel production from renewable energy sources. It will be published Nov. 3 in Science.
"It's a way to take cheap, worthless biomass and turn it into useful fuels and chemicals," said team leader Lanny Schmidt, a Regents Professor of chemical engineering and materials science at the university. "Potentially, the biomass could be used cooking oil or even products from cow manure, yard clippings, cornstalks or trees."
One up-and-coming fuel is biodiesel, which is produced from soy oil. Currently, the key step in conversion of the oil to biodiesel requires the addition of methanol, a fossil fuel. The new process skips the biodiesel step and turns oil straight into hydrogen and carbon monoxide gases by heating it to about 1,000 degrees C. About 70 percent of the hydrogen in the oil is converted to hydrogen gas. Similarly, using a nearly saturated solution of glucose in water, the process heats the sugar so fast that it, too, breaks up into syngas instead of its usual products: carbon and water.
A difficulty in turning plant material into usable fuels has been breaking down the chemical bonds in cellulose--the material that gives plant cell walls their stiffness--to liberate simple sugars that can be fermented
Contact: Mark Cassutt
University of Minnesota