Dr. Bruce Logan, the Kappe professor of environmental engineering and an inventor of the MFC, says, "This MFC process is not limited to using only carbohydrate-based biomass for hydrogen production like conventional fermentation processes. We can theoretically use our MFC to obtain high yields of hydrogen from any biodegradable, dissolved, organic matter -- human, agricultural or industrial wastewater, for example -- and simultaneously clean the wastewater.
"While there is likely insufficient waste biomass to sustain a global hydrogen economy, this form of renewable energy production may help offset the substantial costs of wastewater treatment as well as provide a contribution to nations able to harness hydrogen as an energy source," Logan notes,.
The new approach is described in a paper, "Electrochemically Assisted Microbial Production of Hydrogen from Acetate," released online currently and scheduled for a future issue of Environmental Science and Technology. The authors are Dr. Hong Liu, postdoctoral researcher in environmental engineering; Dr. Stephen Grot, president and founder of Ion Power, Inc.; and Logan. Grot, a former Penn State student, suggested the idea of modifying an MFC to generate hydrogen.
In their paper, the researchers explain that hydrogen production by bacterial fermentation is currently limited by the "fermentation barrier" -- the fact that bacteria, without a power boost, can only convert carbohydrates to a limited amount of hydrogen and a mixture of "dead end" fermentation end products such as acetic and butyric acids.
However, giving the bacteria a small assist with a tiny amoun