Effects of periodically alternating temperatures on performance of single-chamber microbial fuel cells

摘要

Practical applications of microbial fuel cells (MFCs) for wastewater treatment are usually operated over a wide range of temperature, especially day-night temperature difference. Here, MFCs at alternating temperatures were compared with those at constant temperatures. MFCs at 6/18 ℃ reached a steady-state voltage of 0.41 ± 0.05 V at 6 ℃ and 0.36 ± 0.04 V at 18 ℃, which were lower than that of MFCs at 18/30 ℃ (0.42 ± 0.01 V at 18 ℃ and 0.47 ± 0.02 V at 30 ℃). MFCs at 18/30 ℃ produced the highest power density of 2169 ± 82 mW m~(-2) at 30 ℃, even higher than that of MFCs at constant temperature 30 ℃. Moreover, MFCs at 6/18 ℃ and 18/30 ℃ obtained a comparable coulombic efficiencies (94.6 ± 5.2%, 83.2 ± 4.1%, respectively) compared with MFCs at constant temperatures (86.3 ± 7.3% at 18 ℃ and 84.1 ± 5.5% at 30 ℃). These results demonstrate that MFCs could be successfully adapted for use under day-night temperature difference conditions.