CATHODES FOR SEDIMENT MICROBIAL FUEL CELLS

摘要

Plant microbial fuel cells (P-MFCs), and more general sediment microbial fuel cells, make use of electrogenic metabolism in anoxic soils and sediments. Electricigenic micro organisms are able to respire organic carbon from the soil or sediment with anelectrode as electron acceptor. The power output of Plant MFCs is defined by a vast number of factors among others; coulombic and energetic efficiency of the anodic and cathodic reactions, mass and charge transport to and from the electrodes and conductivity of the liquid and sediment. In this work the focus is on the cathode. In a conventional sediment system an oxygen reducing cathode is placed in the above water layer. In this new concept a drain tube was filled with granules and placed in the sediment surrounded by the anode electrode granules. This concept is compared with a conventional floating cathode and with a cathode made of a tubular cation exchange membrane buried in the sediment.