A team of Penn State and society Ion Power (Delaware) has developed a microbial fuel cell (MFC) allowing both to degrade the organic matter and produce hydrogen.
The classic MFC (developed to offset wastewater treatment costs) generate electricity from the redox reactions involved in the process of degradation of organic waste by bacteria.
The new device, called BEAMR for Assisted Microbial Reactor-BioElectrochemically, based in turn on using the hydrogen produced by bacterial fermentation. Under normal conditions, this process converts the carbohydrate compounds in a limited amount of hydrogen and type of waste acetic acid. By applying a low voltage (about 250 mV) to a MFC anaerobic, Bruce Logan and colleagues, however, are able to increase the electrochemical potential of bacteria and thus their ability to break the molecules by-products of fermentation. They were able to recover the form of hydrogen gas over 90% of protons and electrons from the oxidation of acetate by bacteria. The hydrogen released is itself the fuel for a cell that produces the applied voltage. This simple stimulation can be drawn from biomass four times more hydrogen than the single fermentation.
In theory, the principle experienced by the researchers is not limited to carbohydrate compounds; it could be effective
with any soluble biodegradable organic matter.
NYT 25 / 04 / 05 (Fuel cell hydrogen pulls out of bacteria) source.