A microbial fuel cell (MFC) or biological fuel cell is a bio-electrochemical system that drives a current by using bacteria, and mimicking bacterial interactions found in nature. (2)
This assignment focuses on creating a microbiological fuel cell to create and obtain low voltage electricity by using six different sugars (Glucose, Fructose, Sucrose, Maltose, Galactose) and dry yeast as the micro-organism instead of bacteria.
To generate electrical energy through oxidation of biodegradable organic matter the microbiological cell uses a biochemical oxidation process. This happens in the presence of a biocatalyst. There are many advantages in using microbiological fuel cells. For example the most significant advantage is that they use organic materials to produce electricity. Another advantage is that highly regulated distributions are not required like the ones required by the hydrogen fuel cells. The microbiological cells also have higher conversion efficiency than the enzymatic cells and around 90% of the electrons are harvested by them from the bacterial electron transport system (3).
This topic has aroused my interest as now around the world, using fossil fuels to produce electricity is depleted and other alternatives are considered,which would create lower amount of greenhouse gases, and also because microbial fuel cells represent a clean and renewable energy source.I was also fascinated when we did chapter 9 of our syllabus which is oxidation and reduction I was so enthusiastic to see if there is another way of producing low voltage electricity without using electrodes and their salts/electrolytes. My aim in this experiment is to discover“How different types of sugar (Glucose,Fructose,Sucrose,Maltose and Galactose) used in a microbiological fuel cell affect the amount of voltage that is produced under control conditions, and after this has established,would connecting 3 fuel cells of the sugar that has displayed the best voltage, in series makes the voltage produced tripled?’’
Another aspect that has developedmy interest is the actual working chemistry behind these fuelcells.
Under aerobic conditions, the electrical energy which is present in the bonds of the organic compound are turned into electrical energy by the fuel cells into to energy that can be used, using the reactions of micro-organisms. How these cells work is, when the cell is prepared and set up the protons move in the direction towards the cathode section through the proton exchange membrane to complete the circuit. (4)When the equation taking place inside the fuel cell is considered, it can be expressed as: C6H12O6 (s)+ 6O2 (g)6CO2 (g)+6H2O (l)
When living things metabolize food to supply them with the necessary energy they draw the energy from the substances that are rich in electrons by disengaging them from carbohydrates after which, this reaction takes place.
In microbial catabolism, initially a carbohydrate or any other similar substrate is oxidised without oxygen,...