Electrochemical Study of the Energy Generation Performance of Glucose, Lactose, Sucrose and Starch as Substrates in a Mixed Culture Microbial Fuel Cell

In this research, energy generation performance of glucose, lactose, sucrose and starch as substrates in a mixed culture microbial fuel cell was studied by polarization measurements and electrochemical impedance spectroscopy. Results showed that after operation with a 1000 external resistance, normalized to the anode geometric surface area, output open circuit potential and power levels of the microbial cell are highest for glucose (488mV and 25.3 μW/cm2) followed by lactose (352 mV and 7.5 μW/cm2) then sucrose (302 mV and 5.1 μW/cm2) and finally, starch shows considerably lower output power (158 mV and 2.1 μW/cm2). In other words, for an anodic biofilm which was batch cultured using glucose as the initial substrate, with increasing the complexity of digestion metabolism of the employed hydrocarbon substrates, power levels of the microbial fuel cell significantly decrease which can be attributed to the feasibility of the simple hydrocarbons for biochemical digestion