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DOE OSTI · 1302945

Multi-variable mathematical models for the air-cathode microbial fuel cell system

Ou, Shiqi·Kashima, Hiroyuki·Aaron, Douglas S.·Regan, John M.·Mench, Matthew M.
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Abstract

This research adopted the version control system into the model construction for the single chamber air-cathode microbial fuel cell (MFC) system, to understand the interrelation of biological, chemical, and electrochemical reactions. The anodic steady state model was used to consider the chemical species diffusion and electric migration influence to the MFC performance. In the cathodic steady state model, the mass transport and reactions in a multi-layer, abiotic cathode and multi-bacteria cathode biofilm were simulated. Transport of hydroxide was assumed for cathodic pH change. This assumption is an alternative to the typical notion of proton consumption during oxygen reduction to explain elevated cathode pH. The cathodic steady state model provided the power density and polarization curve performance results that can be compared to an experimental MFC system. Another aspect we considered was the relative contributions of platinum catalyst and microbes on the cathode to the oxygen reduction reaction (ORR). We found simulation results showed that the biocatalyst in a cathode that includes a Pt/C catalyst likely plays a minor role in ORR, contributing up to 8% of the total power calculated by the models.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY59 BASIC BIOLOGICAL SCIENCES97 MATHEMATICS AND COMPUTINGCatalystCathode limitationsComputational simulationElectrochemical reactionsMass transportMicrobial fuel cell

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Ou, Shiqi, Kashima, Hiroyuki, Aaron, Douglas S., Regan, John M., Mench, Matthew M.. 2016-03-10. Multi-variable mathematical models for the air-cathode microbial fuel cell system. https://doi.org/10.1016/j.jpowsour.2016.02.064

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