Wisconsin Team Turns Biomass into Jet Fuel

John Davis

A group of engineers at the University of Wisconsin-Madison has been able to turn biomass into the chemical equivalent of jet fuel, and they’ve been able to do it using a process that actually takes advantage of biomass sugars’ bad habit of degrading.

This press release from the school says a simple process developed by James Dumesic, Steenbock Professor of Chemical and Biological Engineering at UW-Madison, postdoctoral researchers Jesse Bond and David Martin Alonso, and graduate students Dong Wang and Ryan West preserves about 95 percent of the energy from the original biomass, requires little hydrogen input, and captures carbon dioxide under high pressure for future use:

Much of the Dumesic group’s previous research of using cellulosic biomass for biofuels has focused on processes that convert abundant plant-based sugars into transportation fuels. However, in previously studied conversion methods, sugar molecules frequently degrade to form levulinic acid and formic acid — two products the previous methods couldn’t readily transform into high-energy liquid fuels.

The team’s new method exploits sugar’s tendency to degrade. “Instead of trying to fight the degradation, we started with levulinic acid and formic acid and tried to see what we could do using that as a platform,” says Dumesic.

In the presence of metal catalysts, the two acids react to form gamma-valerolactone, or GVL, which now is manufactured in small quantities as an herbal food and perfume additive. Using laboratory-scale equipment and stable, inexpensive catalysts, Dumesic’s group converts aqueous solutions of GVL into jet fuel. “It really is very simple,” says Bond, of the two-step catalytic process. “We can pull off these two catalytic stages, as well as the requisite separation steps, in series, with basic equipment. With very minimal processing, we can produce a pure stream of jet-fuel-range alkenes and a fairly pure stream of carbon dioxide.”

The researchers say the fuel produced is high-energy density, making it better suited for the aviation industry than more conventional ethanol. Now, the team is working on making the process cost-effective.