Simple Sugars Can Be Turned Into a New, Potentially Useful Biofuel
21 Jun, 2007 11:33 am
James Dumesic is a professor of chemical and biological engineering at the University of Wisconsin-Madison in the United States. He has published the results of his study on sugar as an additive to gasoline in this weeks edition of Nature.
We produced a fuel additive (dimethylfuran, DMF) by selectively removing 5 out of the six oxygen atoms of a sugar (fructose). A liquid transportation fuel should have three main characteristics. The fuel must boil at the proper temperature so that it is a liquid in the fuel tank and it is a vapor in the engine, it should have high energy density so that you do not need a very large fuel tank, and the fuel must have low solubility in water so that it does not take up water from the humidity in the air. We find that removing 5 out of the 6 oxygen atoms from a sugar leads to a compound (DMF) that satisfies all of these criteria.
What advantage does this type have over other biofuels?
Letís us compare DMF to ethanol according to the above 3 criteria. Compared to ethanol (which is the current biofuel), DMF boils at 20 C higher temperature, which gives refiners more options in the blending of the gasoline. In this respect, ethanol boils at a temperature that is a little too low. DMF has 40% higher energy density. DMF is hydrophobic (water-hating), which means that the gasoline will not absorb water from the atmosphere.
Are there any kinks that need to be worked out?
Our process works well with fructose. It would be very desirable to make the process work well using glucose as the feed.
Do you see any potential industrial uses?
An excellent use of DMF is as a high octane blending agent for gasoline. However, it will be important to test the safety and environmental issues with using DMF as a fuel before we would consider the wide-spread use of this chemical as a possible blending agent for liquid transportation fuels.
Nature 21 June. Chemistry: New method for making biofuels (pp 982-985)
Interview by: Christopher Le Coq
James Dumesic is a professor of chemical and biological engineering at the University of Wisconsin-Madison.