The influence of operational conditions on the performance of a microbial fuel cell seeded with mesophilic anaerobic sludge

In this work, the influence of operational parameters such as organic load, pH and temperature on power generation and methane production was studied in a continuous flow air-cathode microbial fuel cell (MFC) seeded with mesophilic anaerobic sludge. Power generation was accompanied by methane production, when fed with either glucose or acetate, however the ratio of methane-to-electricity production strongly depended on operational conditions. At a pH of 7, electricity production exhibited an Andrews-like dependence on carbon source concentration, whereas methane production followed a Monod-like dependence. pH-stat tests showed maximal power output at a pH of 6.3, which coincided with a decreased methane production. Cathode heating to 62 °C resulted in increased electricity generation with an insignificant increase in methane production.