SEDIMENT MICROBIAL FUEL CELL BASED BIOSENSOR FOR REAL TIME DETECTION OF CU2+ IN INDUSTRIAL WASTEWATERS – OPERATION AND EFFECTIVENESS

Abstract

Sediment microbial fuel cells (SMFCs) are bio-electrochemical systems in which the anode is placed in the anaerobic sediment and the cathode is immersed in the surface layer of water. Natural exoelectrogenic bacteria decompose organic compounds in sediment, producing electrons and protons. The electrons reach the cathode through an external electrical circuit, while the protons pass through the soil layer, which acts as a kind of membrane. Oxygen is in many cases the preferred electron acceptor due to its presence in the cathode region and its high potential. Heavy metal ions and other compounds can also be reduced on the cathode, which will increase the energy generated. Based on the above characteristics, SMFCs would be suitable for application as biosensors for monitoring water pollution with heavy metals. In the present study, the possibility of application of SMFCs as biosensors for water pollution with copper has been studied. A high correlation was found between the concentration of copper ions in the range 0,1 – 100 mg/L and the voltage generated by SMFC. The constructed SMFC based biosensor showed wider detection limits for copper compared to other authors' studies as the coefficient of determination reached 0,9911. Native exoelectrogenic bacteria were represented mainly by Geobacter, Clostridium, Anaeromixobacter and Bacillus.