Designing Microbial Fuel Cells (MFCs) Including Geothrix fermentans and Gluconobacter oxydans Bacteria: Invistegation with Numerical Analysis

In this work, we exhibited the effect of temperature and also cell dimensions on the microbial fuel cells (MFCs) efficiency according to our experimental data. In other words, microbial fuel cells (MFCs) are emerging as promising technologies for applications such as electricity generation. Electroactive (EA) biofilms formed by microorganisms play a central role in bioelectrochemical systems through microbially mediated electrocatalytic reactions. In this study, industrial wastewater containing Geothrix fermentans and Gluconobacter oxydans was evaluated for power generation in MFCs. The effects of temperature, reactor configuration, chamber dimensions, and the distance between anodic and cathodic electrodes on electrical output were systematically investigated. Statistical analyses, including descriptive statistics, correlation, and regression, were performed using SPSS to predict average voltage from the derived regression model. A two-dimensional model was further employed to analyze ionic transport, the distribution of electronic current density, and local reaction rates in both anodic and cathodic chambers. Two types of bacteria were examined: the anaerobic Geothrix fermentans, known for its ability to utilize Fe(III) and other high-potential metals as electron acceptors, and the aerobic Gluconobacter oxydans, tested in a miniature MFC (mini-MFC) system. The results indicated that the aerobic mini-MFC achieved a lower maximum power output than the anaerobic system. Additionally, numerical fitting was performed for MFCs operating under varying temperatures and chamber dimensions. The numerical results showed strong agreement with experimental data, confirming the validity of the proposed model.