Santoro C, Babanova S, Cristiani P, Artyushkova K, Atanassov P, Bergel A, Bretschger O, Brown RK, Carpenter K, Colombo A, Cortese R, Erable B, Harnisch F, Kodali M, Phadke S, Riedle S, Rosa L, Schröder U
How comparable are microbial electrochemical systems around the globe? An electrochemical and microbiological cross-laboratory study.
A cross-laboratory study on microbial fuel cells (MFC) is presented, which involved different institutions around the world is presented. The study aimed to assess the development of autochthone microbial pool enriched from domestic wastewater from different locations, cultivated in identical single chamber MFCs, operated the same way, thereby approaching the idea of developing common standards for MFCs. The MFCs were inoculated with domestic wastewater in different geographic locations. The acclimation stage and consequently the startup time, was longer or shorter depending on the inoculum, but all MFCs reached similar maximum power outputs (55±22 μWcm-2) and COD removal efficiencies (87±9%), despite the diversity of the bacterial communities. It is inferred that the MFCs performance starts when the syntrophic interaction of fermentative and electrogenic bacteria stabilizes under anaerobic conditions at the anode. The generated power is mostly limited by electrolytic conductivity, electrode overpotentials and an unbalanced external resistance. The enriched microbial consortia, although composed of different bacterial groups, share similar functions both on anode and cathode of the different MFCs resulting in similar electrochemical output.