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; Institute for Fuel Cell Innovation, National Research Council of Canada, 4250 Wesbrook Mall, Vancouver, BC V6T 1W5, Canada
International Journal of Hydrogen Energy 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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