Microbial fuel cells
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Transcript of Microbial fuel cells
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B a c t e r i a a s L i v i n g
b a tt e r i e s ? ? ?
Ever increasing Need for ENERGY
What are the
alternatives to fossil fuels
?
Newer solutions...
Fuel cells
Advantages of Fuel Cells
vs.
Internal Combustion Engines
Unlimited supply of fuel
No reliance on foreign oil
Little or no pollutants
No moving parts
No noise
Bacterium That Eats Radioactive Garbage And Generates Electricity
•Geobacter sulfurreducens possesses extraordinary capabilities to transport electrons and "reduce" metal ions as part of its energy-generating metabolism.
•Bacterium with the potential to bioremediate radioactive metals and generate electricity was found.
Forget Horsepower, Think Cow-Power
• Microbes in about a half a liter of rumen fluid - fermented, liquefied feed extracted from the cow's stomach - produced about 600 milli volts of electricity.
• Some of the micro-organisms found in cow waste could provide a reliable source of electricity.
Sediments at the bottom of Boston Harbor
Iron Breathers
Desulfuromonas acetoxidans
What are they???
• Bioreactor: type of battery
• Produces electrochemical redox energy
• Renewable and sustainable energy
• Converts chemical energy, available in a bio-convertible substrate, directly into electricity
Goal : Produce electricity while simultaneously
degrading organic matter.
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Microbial fuel cells
• Organic matter is oxidized by bacteria creating an electric potential.
• Electrons produced are transferred to anode and flow to cathode.
Microbial fuel cells may use wastewater as a fuel, or more generally a dilute solution of a variety of organic materials in water.
Electron Transport chain
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Anode Chamber– Stores fuel
-->
Cathode Chamber
– Exposed to air<--
M e m b r a n e - Allows for H + passage^
Catalyst Often Platinum
V V
Usually graphite, carbon cloth/paper
Anode
20202020
Biocatalysts
Bacteria-metal reducing bacteria
Heterotrophic, auto heterotrophic, mixed-culture
Cathode
Carbon Rod and Carbon Fiber Electrodes
Proton exchange membrane
• Commonly Nafion or Ultrex ; salt bridges also used
• Barrier between anodic and cathodic chambers
• Must be permeable to charged species, reduce oxygen transfer to anodic chamber
C6
H1
2O
6
6H2O
6 CO
2
24 H+
24e
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As an example, Glucose is used as organic substrate
Anode
24 H+ 24e-
Cathode
Click icon to add picture
Electro active Bacteria
Other species include :
• Shewanella putrefaciens • Aeromonas hydrophila
• Pseudomonas species
Some bacteria, which have pili on their external membrane, are able to transfer their electron production via these pili.
Examples of microbial-based fuel cells
Microbe
Substrate
Mediator
Anode Voltage
E coli Glucose MethyleneBlue
Pt- C-cloth 625mV
Bacillussubtilis
Glucose Thionine VitreousCarbon
640mV
E coli Acetate Neutral red Graphitefelt
250mV
Pseudomonasmethanica
Methane 1-Naphthol-2-Sulfonate indo-2,6 dichlorophenol
Pt-black 550mV
Proteusvulgaris
Sucrose Thionine Carbon rod 350mV
Robotics -Studies in “Gastro bots: Autonomous robots powered by MFC’s could consume food (biomass) as seemingly limitless source of energy
Portable units- power generationMicro pumps-insulin, pain meds, arthritis
Current for-nerve stimulation, hearing aidsHeart pacemaker (cells in series)Renewable and sustainable source of electricity.
Biosensors Aerospace applications aim to generate power and remediate pollutants from human waste aboard exploratory missions with large crews
Powering electronic monitoring devices in remote locations, such as
the bottom of the ocean
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Advanced Water Management Centre ------
constructed a pilot scale microbial fuel cell. The pilot scale plant was built on the site of the Foster's brewery in Yatala, Queensland (Australia).
Urine: Waste Product or Future Power Source? -----
Researchers in the UK are looking into the use of urine as the ‘fuel’ for microbial fuel cells (MFCs), which use bacterial cultures to break down ‘food’ to create power.
IntAct Labs LLC in Cambridge -----
recycling waste products during space missions.
Harvard University ---------
provide power for lighting and other systems in developing nations
Derek Lovley’s Geobactor Project at UMass Amherst ------
looking to create organic batteries that could one day power computers or even vehicles.
Hy-SyEnce Inc. (Fall River) ------
wastewater of food-processing plants
From waste to power in one step!
Towards a promising future…The mechanisms of electron transfer between the microorganisms and the electrode should be elucidated in order to design better electrodes or genetically engineer better microbes for higher rates of electricity production.
Research continues to seek robust microbial biocatalysts, improve design, better electrode materials, more effective mediators
Not marketable yet, but research continues to improve prospects
Thank you!!!
Questions???