Composite Electrode using Graphite and Opuntia imbricata to Develop an Anodophilic Biofilm in a Microbial Fuel Cell

The present study focused on the use of a composite electrode in the anodic compartment to increase energy output and reduce the cost of Microbial Fuel Cell (MFC). In order to transfer electrons by conduction by electrogenic microorganisms to the electrode this have to be in direct contact with the electrode, being this a limitation to MFC due to limited surface area available in electrode. A two-chamber MFC was used, with graphite electrodes, anodic electrode was inserted in a small piece of coyonoztle (Opuntia imbricata). MFC was operated in fedbatch mode during a period of 60 days, using glucose as carbon source glucose (3 g/L), three external loads were used (5.5 KΩ, 1 KΩ and 560 Ω). Maximum voltage, current and power density was obtained for the case of 1 KΩ; 205.88 mV, 139.33 A y 3.43 W.cm2, respectably.