Anolyte recirculation effects in buffered and unbuffered single-chamber air-cathode microbial fuel cells.
Two identical microbial fuel cells (MFCs) with a floating air-cathode were operated under either buffered (MFC-B) or bufferless (MFC-BL) conditions to investigate anolyte recirculation effects on enhancing proton transfer. With an external resistance of 50 Ω and recirculation rate of 1.0 ml/min, MFC-BL had a 27% lower voltage (9.7% lower maximal power density) but a 64% higher Coulombic efficiency (CE) than MFC-B. MFC-B had a decreased voltage output, batch time, and CE with increasing recirculation rate resulting from more oxygen transfer into the anode. However, increasing the recirculation rate within a low range significantly enhanced proton transfer in MFC-BL, resulting in a higher voltage output, a longer batch time, and a higher CE. A further increase in recirculation rate decreased the batch time and CE of MFC-BL due to excess oxygen transfer into anode outweighing the proton-transfer benefits. The unbuffered MFC had an optimal recirculation rate of 0.35 ml/min.
['Zhang|Liang|L|', 'Zhu|Xun|X|', 'Kashima|Hiroyuki|H|', 'Li|Jun|J|', 'Ye|Ding-Ding|DD|', 'Liao|Qiang|Q|', 'Regan|John M|JM|']
D000388:Air D061249:Batch Cell Culture Techniques D001674:Bioelectric Energy Sources D057919:Biological Oxygen Demand Analysis D004560:Electricity D004566:Electrodes D005240:Feasibility Studies D006863:Hydrogen-Ion Concentration D011522:Protons
Anolyte recirculation Microbial fuel cell Bufferless Proton transfer Oxygen transfer