Now, chemical engineers at the University of Wisconsin-Madison have developed a new process that produces hydrogen fuel from plants. This source of hydrogen is non-toxic, non-flammable and can be safely transported in the form of sugars.
Writing this week (Aug. 29) in the journal Nature, research scientist Randy Cortright, graduate student Rupali Davda and professor James Dumesic describe a process by which glucose, the same energy source used by most plants and animals, is converted to hydrogen, carbon dioxide, and gaseous alkanes with hydrogen constituting 50 percent of the products. More refined molecules such as ethylene glycol and methanol are almost completely converted to hydrogen and carbon dioxide.
"The process should be greenhouse-gas neutral," says Cortright. "Carbon dioxide is produced as a byproduct, but the plant biomass grown for hydrogen production will fix and store the carbon dioxide released the previous year."
Glucose is manufactured in vast quantities -- for example, in the form of corn syrup -- from corn starch, but can also be made from sugar beets, or low-cost biomass waste streams like paper mill sludge, cheese whey, corn stover or wood waste.
While hydrogen yields are higher for more refined molecules, Dumesic says glucose derived from waste biomass is likely to be the more practical candidate for cost effectively generating power.
"We believe we can make improvements to the catalyst and reactor design that will increase the amount of hydrogen we get from glucose," says Dumesic. "The alkane byproduct could be used to power an internal combustion engine or a solid-oxide fuel cell. Very lit
Contact: James Dumesic
University of Wisconsin-Madison