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Published on: July 24, 2018
Anode microbial communities produced by changing from microbial fuel cell to microbial electrolysis cell operation
Patrick D Kiely1, Roland Cusick, Douglas F Call
1Department of Civil and Environmental Engineering, H(2)E Center, 131 Sackett Building, The Pennsylvannia State University, University Park, PA 16802, USA.
Bioresource Technology
|June 18, 2010
Summary
Shifting microbial fuel cells (MFCs) to microbial electrolysis cells (MECs) altered anode microbial communities, favoring specific Geobacter species. Higher microbial diversity in MFCs did not necessarily correlate with increased electrical current generation.
Area of Science:
- Microbiology
- Environmental Science
- Electrochemistry
Background:
- Microbial fuel cells (MFCs) and microbial electrolysis cells (MECs) are bioelectrochemical systems.
- Distinct operating conditions, including oxygen presence and gas evolution, differentiate MFCs and MECs.
- Understanding microbial community shifts is crucial for optimizing these systems.
Purpose of the Study:
- To investigate the impact of transitioning from MFCs to MECs on anode microbial communities.
- To determine how different organic matter sources affect microbial community composition under varying conditions.
- To assess the relationship between microbial diversity and current generation in these systems.
Main Methods:
- Utilized 16S rRNA gene clone libraries to analyze anode microbial communities.
- Compared microbial communities in reactors under MFC and MEC conditions.
- Fed reactors with different substrates: acetic acid, potato wastewater, and dairy manure wastewater.
Main Results:
- In acetic acid-fed reactors, species richness and diversity decreased, while Geobacter sulfurreducens increased when shifted to MEC conditions.
- With potato wastewater, Geobacteraceae proportions remained stable, but G. sulfurreducens decreased and Geobacter metallireducens increased in MECs.
- A dairy manure wastewater-fed MFC showed high diversity but low power and failed to generate current as an MEC.
Conclusions:
- The microbial electrolysis cell (MEC) environment induces significant changes in Geobacter species composition.
- Increased microbial species diversity in microbial fuel cells (MFCs) does not directly correlate with higher current output.
- Substrate type influences the microbial community response to the transition from MFC to MEC operation.
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