Responses from freshwater sediment during electricity generation using microbial fuel cells

Abstract

In a two-electrode system, freshwater sediment was used as a fuel to examine the relationship between current generation and organic matter consumption with different types of electrode. Sediment microbial fuel cells using porous electrodes showed a superior performance in terms of generating current when compared with the use of non-porous electrodes. The maximum current densities with thicker and thin porous electrodes were 45.4 and 37.6 mA m-2, respectively, whereas the value with nonporous electrodes was 13.9 mA m-2. The amount of organic matter removed correlated with the current produced. The redox potential in the anode area under closedcircuit conditions was ?246.3 ± 67.7 mV, while that under open-circuit conditions only reached -143.0 ± 7.18 mV. This suggests that an application of this system in organicrich sediment could provide environmental benefits such as decreasing organic matter and prohibiting methane emission in conjunction with electricity production via an anaerobic oxidation process.