Kinetic experiments for evaluating the nernst-monod model for anode-respiring bacteria (ARB) in a biofilm anode

Cesar Torres, Andrew Marcus, Prathap Parameswaran, Bruce Rittmann

Research output: Contribution to journalArticle

152 Citations (Scopus)

Abstract

Anode-respiring bacteria (ARB) are able to transfer electrons from reduced substrates to a solid electrode. Previously, we developed a biofilm model based on the Nernst-Monod equation to describe the anode potential losses of ARB that transfer electrons through a solid conductive matrix. In this work, we develop an experimental setup to demonstrate how well the Nernst-Monod equation is able to represent anode potential losses in an ARB biofilm. We performed low-scan cyclic voltammetry (LSCV) throughout the growth phase of an ARB biofilm on a graphite electrode growing on acetate in continuous mode. The jV response of 9 LSCVs corresponded well to the Nernst-Monod equation, and the half-saturation potential (EKA) was -0.425 ± 0.002 V vs Ag/AgCl at 30°C (-0.155 ± 0.002 V vs SHE). Anode-potential losses from the potential of acetate reached ∼0.225 V at current density saturation, and this loss was determined by our microbial community's EKA value. The LSCVs at high current densities showed no significant deviation from the Nernst-Monod ideal shape, indicating that the conductivity of the biofilm matrix (κbio) was high enough (≥0.5 mS/cm) that potential loss did not affect the performance of the biofilm anode. Our results confirm the applicability of the Nernst-Monod equation for a conductive biofilm anode and give insights of the processes that dominate anode potential losses in microbial fuel cells.

Original languageEnglish (US)
Pages (from-to)6593-6597
Number of pages5
JournalEnvironmental Science and Technology
Volume42
Issue number17
DOIs
StatePublished - Sep 1 2008

Fingerprint

Biofilms
biofilm
Bacteria
Anodes
kinetics
bacterium
Kinetics
experiment
Experiments
density current
acetate
electrode
saturation
electron
matrix
fuel cell
Acetates
Current density
graphite
loss

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Science(all)
  • Environmental Chemistry
  • Chemistry(all)

Cite this

@article{c444ebdfb48d4befa7cbc6ea44fbba2b,
title = "Kinetic experiments for evaluating the nernst-monod model for anode-respiring bacteria (ARB) in a biofilm anode",
abstract = "Anode-respiring bacteria (ARB) are able to transfer electrons from reduced substrates to a solid electrode. Previously, we developed a biofilm model based on the Nernst-Monod equation to describe the anode potential losses of ARB that transfer electrons through a solid conductive matrix. In this work, we develop an experimental setup to demonstrate how well the Nernst-Monod equation is able to represent anode potential losses in an ARB biofilm. We performed low-scan cyclic voltammetry (LSCV) throughout the growth phase of an ARB biofilm on a graphite electrode growing on acetate in continuous mode. The jV response of 9 LSCVs corresponded well to the Nernst-Monod equation, and the half-saturation potential (EKA) was -0.425 ± 0.002 V vs Ag/AgCl at 30°C (-0.155 ± 0.002 V vs SHE). Anode-potential losses from the potential of acetate reached ∼0.225 V at current density saturation, and this loss was determined by our microbial community's EKA value. The LSCVs at high current densities showed no significant deviation from the Nernst-Monod ideal shape, indicating that the conductivity of the biofilm matrix (κbio) was high enough (≥0.5 mS/cm) that potential loss did not affect the performance of the biofilm anode. Our results confirm the applicability of the Nernst-Monod equation for a conductive biofilm anode and give insights of the processes that dominate anode potential losses in microbial fuel cells.",
author = "Cesar Torres and Andrew Marcus and Prathap Parameswaran and Bruce Rittmann",
year = "2008",
month = "9",
day = "1",
doi = "10.1021/es800970w",
language = "English (US)",
volume = "42",
pages = "6593--6597",
journal = "Environmental Science & Technology",
issn = "0013-936X",
publisher = "American Chemical Society",
number = "17",

}

TY - JOUR

T1 - Kinetic experiments for evaluating the nernst-monod model for anode-respiring bacteria (ARB) in a biofilm anode

AU - Torres, Cesar

AU - Marcus, Andrew

AU - Parameswaran, Prathap

AU - Rittmann, Bruce

PY - 2008/9/1

Y1 - 2008/9/1

N2 - Anode-respiring bacteria (ARB) are able to transfer electrons from reduced substrates to a solid electrode. Previously, we developed a biofilm model based on the Nernst-Monod equation to describe the anode potential losses of ARB that transfer electrons through a solid conductive matrix. In this work, we develop an experimental setup to demonstrate how well the Nernst-Monod equation is able to represent anode potential losses in an ARB biofilm. We performed low-scan cyclic voltammetry (LSCV) throughout the growth phase of an ARB biofilm on a graphite electrode growing on acetate in continuous mode. The jV response of 9 LSCVs corresponded well to the Nernst-Monod equation, and the half-saturation potential (EKA) was -0.425 ± 0.002 V vs Ag/AgCl at 30°C (-0.155 ± 0.002 V vs SHE). Anode-potential losses from the potential of acetate reached ∼0.225 V at current density saturation, and this loss was determined by our microbial community's EKA value. The LSCVs at high current densities showed no significant deviation from the Nernst-Monod ideal shape, indicating that the conductivity of the biofilm matrix (κbio) was high enough (≥0.5 mS/cm) that potential loss did not affect the performance of the biofilm anode. Our results confirm the applicability of the Nernst-Monod equation for a conductive biofilm anode and give insights of the processes that dominate anode potential losses in microbial fuel cells.

AB - Anode-respiring bacteria (ARB) are able to transfer electrons from reduced substrates to a solid electrode. Previously, we developed a biofilm model based on the Nernst-Monod equation to describe the anode potential losses of ARB that transfer electrons through a solid conductive matrix. In this work, we develop an experimental setup to demonstrate how well the Nernst-Monod equation is able to represent anode potential losses in an ARB biofilm. We performed low-scan cyclic voltammetry (LSCV) throughout the growth phase of an ARB biofilm on a graphite electrode growing on acetate in continuous mode. The jV response of 9 LSCVs corresponded well to the Nernst-Monod equation, and the half-saturation potential (EKA) was -0.425 ± 0.002 V vs Ag/AgCl at 30°C (-0.155 ± 0.002 V vs SHE). Anode-potential losses from the potential of acetate reached ∼0.225 V at current density saturation, and this loss was determined by our microbial community's EKA value. The LSCVs at high current densities showed no significant deviation from the Nernst-Monod ideal shape, indicating that the conductivity of the biofilm matrix (κbio) was high enough (≥0.5 mS/cm) that potential loss did not affect the performance of the biofilm anode. Our results confirm the applicability of the Nernst-Monod equation for a conductive biofilm anode and give insights of the processes that dominate anode potential losses in microbial fuel cells.

UR - http://www.scopus.com/inward/record.url?scp=50849127130&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=50849127130&partnerID=8YFLogxK

U2 - 10.1021/es800970w

DO - 10.1021/es800970w

M3 - Article

C2 - 18800535

AN - SCOPUS:50849127130

VL - 42

SP - 6593

EP - 6597

JO - Environmental Science & Technology

JF - Environmental Science & Technology

SN - 0013-936X

IS - 17

ER -