Microbial Reactor Produces H2

Two researchers from Penn State and a scientist from Ion Power have developed a process that enables bacteria to extract four times as much hydrogen directly from biomass than can be generated typically by fermentation alone. The process uses an electrically-assisted microbial fuel cell (MFC) that does not require oxygen to operate.

In typical fermentation, bacteria produce a limited amount of hydrogen as well as a mixture of useless acetic and butyric acids. The new process gives the bacteria an electric "boost" - approximately 0.25 volts - that allows them to convert acetic acid into carbon dioxide and hydrogen. Researchers call the hydrogen-producing MFC a BioElectrochemically-Assisted Microbial Reactor, or BEAMR. While producing hydrogen, the BEAMR cleans the wastewater used as its feedstock. It uses about one-tenth of the voltage needed for electrolysis, the hydrogen-producing process that uses electricity to break down water into hydrogen and oxygen.