UW Scientists Develop a More Efficient Way to Make Ethanol
by Annie Shao, age 16
Currently, fossil fuels are the main fuel source humans use. The problem is that fossil fuels take millions of years to form and are non-renewable. Scientists and entrepreneurs continue to examine the potential of ethanol as a fuel source.
Ethanol is an alcohol that can serve as a renewable energy source. Usually derived from corn, it contains high sugar levels that can easily be fermented into alcohol. Critics of corn ethanol, however, feel that using corn for this would take a toll on world food supplies. There are also questions about harm to the environment and effects on agriculture.
A possible solution to this problem is making cellulosic ethanol, which comes from the parts of crops that people do not eat, like the stalks and leaves of corn. Non-food crops like switchgrass can also be used. This process uses lignocellulose, a structural material in plants that is one of the most plentiful organic substances on Earth.
Cellulosic ethanol is more challenging to produce, since the lignocellulose has to be degraded into sugars before fermentation can take place. In addition, the method uses expensive and dangerous enzymes as well as concentrated acids.
Ronald T. Raines and Joseph B. Binder, two scientists from the University of Wisconsin-Madison, have found a way to make the production of cellulosic ethanol more efficient. They propose a method using ionic liquid, a salt with a low melting point, which, combined with water and acids of lower concentrations can produce sugars.
Raines and Binder discovered that water is a crucial factor in the procedure, since it prevents sugars from reacting with other chemicals in the process, which would yield undesired compounds. Their process generates about as much ethanol as less efficient methods that use enzymes.
Even though their research is still in progress, Raines and Binder’s ideas have far-reaching implications for bio-fuels. Their process of producing ethanol would make fuel from what would otherwise be agricultural waste.
[Source: The New York Times]