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Title: Full cell simulation and the evaluation of the buffer system on air-cathode microbial fuel cell

Abstract

This paper presents a computational model of a single chamber, air-cathode MFC. The model considers losses due to mass transport, as well as biological and electrochemical reactions, in both the anode and cathode half-cells. Computational fluid dynamics and Monod-Nernst analysis are incorporated into the reactions for the anode biofilm and cathode Pt catalyst and biofilm. The integrated model provides a macro-perspective of the interrelation between the anode and cathode during power production, while incorporating microscale contributions of mass transport within the anode and cathode layers. Model considerations include the effects of pH (H +/OH transport) and electric field-driven migration on concentration overpotential, effects of various buffers and various amounts of buffer on the pH in the whole reactor, and overall impacts on the power output of the MFC. The simulation results fit the experimental polarization and power density curves well. Further, this model provides insight regarding mass transport at varying current density regimes and quantitative delineation of overpotentials at the anode and cathode. Altogether, this comprehensive simulation is designed to accurately predict MFC performance based on fundamental fluid and kinetic relations and guide optimization of the MFC system.

Authors:
 [1];  [2];  [3];  [2];  [3]
  1. Oak Ridge National Lab. (ORNL), Knoxville, TN (United States)
  2. The Pennsylvania State Univ., University Park, PA (United States)
  3. The Univ. of Tennessee, Knoxville, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
1345011
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Power Sources
Additional Journal Information:
Journal Volume: 347; Journal Issue: C; Journal ID: ISSN 0378-7753
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
30 DIRECT ENERGY CONVERSION; microbial fuel cell; computational simulation; mass transport; buffer system; pH; concentration overpotential

Citation Formats

Ou, Shiqi, Kashima, Hiroyuki, Aaron, Douglas S., Regan, John M., and Mench, Matthew M. Full cell simulation and the evaluation of the buffer system on air-cathode microbial fuel cell. United States: N. p., 2017. Web. doi:10.1016/j.jpowsour.2017.02.031.
Ou, Shiqi, Kashima, Hiroyuki, Aaron, Douglas S., Regan, John M., & Mench, Matthew M. Full cell simulation and the evaluation of the buffer system on air-cathode microbial fuel cell. United States. doi:10.1016/j.jpowsour.2017.02.031.
Ou, Shiqi, Kashima, Hiroyuki, Aaron, Douglas S., Regan, John M., and Mench, Matthew M. Thu . "Full cell simulation and the evaluation of the buffer system on air-cathode microbial fuel cell". United States. doi:10.1016/j.jpowsour.2017.02.031. https://www.osti.gov/servlets/purl/1345011.
@article{osti_1345011,
title = {Full cell simulation and the evaluation of the buffer system on air-cathode microbial fuel cell},
author = {Ou, Shiqi and Kashima, Hiroyuki and Aaron, Douglas S. and Regan, John M. and Mench, Matthew M.},
abstractNote = {This paper presents a computational model of a single chamber, air-cathode MFC. The model considers losses due to mass transport, as well as biological and electrochemical reactions, in both the anode and cathode half-cells. Computational fluid dynamics and Monod-Nernst analysis are incorporated into the reactions for the anode biofilm and cathode Pt catalyst and biofilm. The integrated model provides a macro-perspective of the interrelation between the anode and cathode during power production, while incorporating microscale contributions of mass transport within the anode and cathode layers. Model considerations include the effects of pH (H+/OH– transport) and electric field-driven migration on concentration overpotential, effects of various buffers and various amounts of buffer on the pH in the whole reactor, and overall impacts on the power output of the MFC. The simulation results fit the experimental polarization and power density curves well. Further, this model provides insight regarding mass transport at varying current density regimes and quantitative delineation of overpotentials at the anode and cathode. Altogether, this comprehensive simulation is designed to accurately predict MFC performance based on fundamental fluid and kinetic relations and guide optimization of the MFC system.},
doi = {10.1016/j.jpowsour.2017.02.031},
journal = {Journal of Power Sources},
number = C,
volume = 347,
place = {United States},
year = {Thu Feb 23 00:00:00 EST 2017},
month = {Thu Feb 23 00:00:00 EST 2017}
}

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