Microbial Fuel Cell (MFC) Jacopo Paini 1108233 MSc Renewable Bio-Energy

Microbial Fuel Cell History of MFCs How do they work ? Recent Developments Conclusion Source: Microbial Fuel Cells: Recent Trends

History Microbial Fuel Cell Potter (1911) Electricity generation using E.coli Cohen (1931) MFC connection in series. Suzuki project (1976)  C.butyricum Hydrogen production (Microbial electrolysis Cells) Kim (1990’s)  Schewanella Putrefaciens Logan (now) Pioneer in projecting reactor designs and theoretical models using also salted water

(Glucose) C12H22O11+ 13H2O  12CO2 + 48H+ + 48e- Microbial Fuel Cell Redox Reaction Source: http://cikguwong.blogspot.co.uk/2011/06/chemistry-form-5-chapter-3-redox.html In MFC: In this case O2 is the final acceptor of electrons Final Product is Water In absence of Oxygen: (Glucose) C12H22O11+ 13H2O  12CO2 + 48H+ + 48e- The final electron acceptor could be Fe(III) or nitrate, so called mediator because the electrons pass to H+ and the final product is H2 8H+ + 8e-(Mediator)  4H2

Geobacter sulfurreducens Microbial Fuel Cell (a) Oxidation of Fuel (b) Transfer of electrons to electrodes through microbes (c) Diffusion of protons to the cathode (d) Reaction in Cathode chamber (e) Diffusion of Oxygen Bacteria can also transfer electrons to anodes either directly as a biofilm http://microbialenergysolutions.weebly.com/our-solution.html Geobacter sulfurreducens

Recent Improvements Microbial Fuel Cell Professor Torres (ASU) new material for IEM: AS-4 (High Anion Exchange Capacity) Professor Logan (PSU) uses water with ammonium bicarbonate salt to augment the energy produced (5.6 W/m2) It doesn’t smear the membrane Easy to remove by evaporation (110°F = 43.33°C) Improved efficiency Professor Burgess Newcastle University discover of new microbe’s combination achieved. Nafion © Polymeric Structure http://www.dailymail.co.uk/sciencetech/article-2104727/Space-bacteria-British-river-new-power-source-world.html

Why are Important ? Microbial Fuel Cell Promising area of study for electronic small devices Energy continuously (as long the substrate is provided) Energy from wastewaters Reduced imported energy Theoretically without emissions Source: http://www.scientificamerican.com/article.cfm?id=microbial-fuel-cell-treats-wastewater-harvests-energy

Thank you for the Attention Microbial Fuel Cell Thank you for the Attention References: Khera, J. and Chandra A. (2012); Microbial Fuel Cells: Recent Trends