Hydrogen Production in a Single Chamber Microbial Electrolysis Cell Lacking a Membrane

Hydrogen gas can be produced by electrohydrogenesis in microbial electrolysis cells (MECs) at greater yields than fermentation and at greater energy efficiencies than water electrolysis. It has been assumed that a membrane is needed in an MEC to avoid hydrogen losses due to bacterial consumption of the product gas. However, high cathodic hydrogen recoveries (78 +/- 1% to 96 +/- 1%) were achieved in an MEC despite the absence of a membrane between the electrodes (applied voltages of 0.3 0.6 V. These results demonstrate that high hydrogen recovery and production rates are possible in a single chamber MEC without a membrane, potentially reducing the costs of these systems and allowing for new and simpler designs.