Electricity generation from synthesis gas by microbial processes: CO fermentation and microbial fuel cell technology

Area of Science:

• Microbiology
• Electrochemistry
• Biotechnology

Background:

• Conventional methods for converting synthesis gas (syngas) to electricity often rely on metal catalysts, which can be expensive and have drawbacks.
• Carbon monoxide (CO) is a major component of syngas and presents a potential energy source.
• Microbial fuel cells (MFCs) offer a sustainable alternative for energy harvesting.

Purpose of the Study:

• To establish a microbiological process for electricity generation from carbon monoxide (CO).
• To investigate the potential of using specific microorganisms to convert CO into electrical energy.
• To demonstrate the feasibility of using microbial fuel cells (MFCs) for syngas-to-electricity conversion.

Main Methods:

• Enrichment of a CO fermenter using carbon monoxide as the sole carbon source.
• Identification of enriched microorganisms using DGGE/DNA sequencing, revealing Acetobacterium spp.
• Continuous operation of the fermenter and feeding of products to a microbial fuel cell (MFC) for electricity generation.

Main Results:

• Acetobacterium spp. were successfully enriched from anaerobic digester fluid using CO as the sole carbon source.
• The microbial fuel cell (MFC) generated electricity when continuously fed with products from the CO fermenter.
• While the conversion yield was low, the process demonstrated the principle of microbial electricity generation from CO.

Conclusions:

• A viable microbiological process for harvesting electricity from carbon monoxide (CO) was established.
• Acetobacterium spp. can be utilized in a microbial fuel cell (MFC) system for CO conversion to electricity.
• This microbial approach offers an alternative to conventional metal catalysts for syngas-to-electricity conversion, avoiding their associated drawbacks.