Adaptations of a Novel Microbial Fuel Cell Design for Electrical Production and Bacterial Load Reduction

Abstract

Nine microbial fuel cells were constructed using different cathode materials and carbon cloth anodes for voltage production from a pig manure substrate. The cathode materials included: copper, brass, carbon cloth, titanium, sheet lead, galvanized low carbon steel, low carbon steel, aluminum foil‐faced fiberglass, and stainless steel. The open circuit voltage (OCV) of each of these cells was collected over time. The internal resistance (Rint) was measured using a decade resistance box at periodic intervals. From this information, the current (I) could be calculated. Data collection on six of the cells was discontinued due to low voltage production. The remaining three cells (copper, brass, and carbon cloth) continuously generated an OCV for over eighteen weeks. As compared to the discontinued cells, the copper and brass cathode cells produced consistently higher voltages (approximately 0.65 V and 0.55 V) and had currents in the range of 15 to 25 mA and 8 to 10 mA, respectively, for the majority of their life spans. The carbon cloth cathode cell produced high voltages (approximately 0.68 V), but displayed a current of less than 10 mA. These three cells displayed an average bacterial load reduction of approximately 93.6%. This information can be applied towards the development of more efficient microbial fuel cells with higher OCV and current outputs, and cells with increasing efficacy at reducing the bacterial load.

Key findings

• ▸Copper and brass cathode cells produced consistently higher voltages (approximately 0.65 V and 0.55 V) and had currents in the range of 15 to 25 mA and 8 to 10 mA, respectively.
• ▸Carbon cloth cathode cell produced high voltages (approximately 0.68 V), but displayed a current of less than 10 mA.
• ▸Six cells were discontinued due to low voltage production.

Keywords

Identifiers

DOI

10.1096/fasebj.24.1_supplement.1065.1

Journal

The FASEB Journal

Year

2010