Effect of external resistance on bacterial diversity and metabolism in cellulose-fed microbial fuel cells
2011
Rismani-Yazdi, Hamid | Christy, Ann D. | Carver, Sarah M. | Yu, Zhongtang | Dehority, Burk A. | Tuovinen, O. H.
External resistance affects the performance of microbial fuel cells (MFCs) by controlling the flow of electrons from the anode to the cathode. The purpose of this study was to determine the effect of external resistance on bacterial diversity and metabolism in MFCs. Four external resistances (20, 249, 480, and 1000Ω) were tested by operating parallel MFCs independently at constant circuit loads for 10weeks. A maximum power density of 66mWm⁻² was achieved by the 20Ω MFCs, while the MFCs with 249, 480, and 1000Ω external resistances produced 57.5, 27, and 47mWm⁻², respectively. Denaturing gradient gel electrophoresis analysis of partial 16S rRNA genes showed clear differences between the planktonic and anode-attached populations at various external resistances. Concentrations of short chain fatty acids were higher in MFCs with larger circuit loads, suggesting that fermentative metabolism dominated over anaerobic respiration using the anode as the final electron acceptor.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library