Modeling and validation of single-chamber microbial fuel cell cathode biofilm growth and response to oxidant gas composition

Journal Article · Mon Aug 15 00:00:00 EDT 2016 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2016.08.007· OSTI ID:1302944

Ou, Shiqi ^[1]; Zhao, Yi ^[2]; Aaron, Douglas S. ^[3]; Regan, John M. ^[4]; Mench, Matthew M. ^[3]

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1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace and Biomedical Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). National Transportation Research Center
2. Pennsylvania State Univ., University Park, PA (United States). Dept of Civil & Environmental Engineering
3. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Mechanical, Aerospace and Biomedical Engineering
4. Pennsylvania State Univ., University Park, PA (United States). Dept of Civil & Environmental Engineering

This work describes experiments and computational simulations to analyze single-chamber, air-cathode microbial fuel cell (MFC) performance and cathodic limitations in terms of current generation, power output, mass transport, biomass competition, and biofilm growth. Steady-state and transient cathode models were developed and experimentally validated. Two cathode gas mixtures were used to explore oxygen transport in the cathode: the MFCs exposed to a helium-oxygen mixture (heliox) produced higher current and power output than the group of MFCs exposed to air or a nitrogen-oxygen mixture (nitrox), indicating a dependence on gas-phase transport in the cathode. Multi-substance transport, biological reactions, and electrochemical reactions in a multi-layer and multi-biomass cathode biofilm were also simulated in a transient model. The transient model described biofilm growth over 15 days while providing insight into mass transport and cathodic dissolved species concentration profiles during biofilm growth. Lastly, simulation results predict that the dissolved oxygen content and diffusion in the cathode are key parameters affecting the power output of the air-cathode MFC system, with greater oxygen content in the cathode resulting in increased power output and fully-matured biomass.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: ORNL Program Development; US Army Research Office; USDOE
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1302944
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Journal Issue: C Vol. 328; ISSN 0378-7753
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
97 MATHEMATICS AND COMPUTING
Cathodic biofilm growth
High performance computing
Microbial fuel cell
Oxygen transport
Transient model