The Role of Cation and Anion Exchange Membranes on Power Generation and Nutrient Removal in a Microalgae-Assisted Microbial Fuel Cell

Microalgae have a wide array of bioelectrochemical wastewater treatment applications, including their role as an in-situ oxygen supplier in the cathode chamber of a double-chamber microbial fuel cell (MFC). In this application, oxygen produced from the microalgae serves as a terminal electron acceptor to readily supplement the cathodic reduction reaction, which is the key to the sustenance of electron generation in MFCs. Furthermore, increased rates of nutrient removal (nitrogen and/or phosphorus) in the MFC can be observed. In this study, the growth and performance of cathodic microalgae, based on the above parameters, are examinedin MFCs containing a cation exchange membrane (CEM) and an anion exchange membrane (AEM). Influent of a municipal wastewater treatment plant after the primary treatment is utilized as a substrate in the anode chambers, and pre-cultivated microalgae (Chlorella vulgaris) are introduced into the cathode chambers of both MFCs. The performance of the MFCs is constantly analyzed usingvarious analytical methods. Phosphate buffers are utilized to manage pH spikes that could occur in the reactors. This study provides a unique understanding of how compositional differences in the cathodic substrate, imposed by the type of membrane, affect the algae’s influence on the cathodic reduction reaction. The study's findings can supplement the establishment of more efficient MFC configurations to address certain limitations, such as low power density, and facilitate progressionin the utilization of MFCs in large-scale wastewater treatment plants.