Conception and optimization of a membrane electrode assembly microbial fuel cell (MEA-MFC) for treatment of domestic wastewater

A membrane electrode assembly (MEA) for microbial fuel cells (MEA-MFC) was developed for continuous electricity production while treating domestic wastewater concurrently. It was optimized via three upgraded versions (noted alpha, beta and gamma) in terms of design (current collectors, hydrophilic separator nature) and operating conditions (hydraulic retention time, external resistance, aeration rate, recirculation). An overall rise of power by over 100% from version alpha to gamma shows the importance of factors such as the choice of proper construction materials and prevention of short-circuits. A power of 2.5 mW was generated with a hydraulic retention time of 2.3 h when a Selemion proton exchange membrane was used as a hydrophilic separator in the MEA and 2.8 mW were attained with a reverse osmosis membrane. The MFC also showed a competitive value of internal resistance (approximate to 40-50 Omega) as compared to the literature, especially considering its large volume (3 L). However, the operation of our system in a complete loop where the anolyte was allowed to trickle over the cathode (version gamma) resulted in system failure.