Article

High rate membrane-less microbial electrolysis cell for continuous hydrogen production

Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, QC H2P 2R2, Canada
International Journal of Hydrogen Energy (Impact Factor: 2.93). 01/2009; DOI: 10.1016/j.ijhydene.2008.11.003

ABSTRACT This study demonstrates hydrogen production in a membrane-less continuous flow microbial electrolysis cell (MEC) with a gas-phase cathode. The MEC used a carbon felt anode and a gas diffusion cathode with a Pt loading of 0.5 mg cm−2. No proton exchange membrane (PEM) was used in the setup. Instead, the electrodes were separated by a J-cloth. The absence of a PEM as well as a short distance maintained between the electrodes (0.3 mm) resulted in a low internal resistance of 19 Ω. Due to an improved design, the volumetric hydrogen production rate reached 6.3 LSTP d−1. In spite of the PEM absence, methane concentration in the gas collection chamber was below 2.1% and the presence of hydrogen in the anodic chamber was never observed.

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