Treatment of Real Wastewater in a Dual-Chamber Microbial Fuel Cell: Comparison of Scenedesmus acutus and a Native Microbial Consortium

The growing deterioration of water resources and the energy requirements of conventional wastewater treatment technologies have increased interest in systems that combine organic matter removal with bioelectrochemical conversion. This study evaluated a laboratory-scale dual-chamber microbial fuel cell (MFC) operated with real wastewater using Scenedesmus acutus (S. acutus) and a native microbial consortium as anodic biocatalysts at 25 and 30 °C. The system was assessed through continuous monitoring of voltage, pH, temperature, and CH4, H2, and CO2 signals in the anodic headspace, together with physicochemical characterization and chemical oxygen demand (COD) removal. COD removal efficiencies of 33.7 and 30.3% were obtained for S. acutus at 25 and 30 °C, respectively, whereas the native microbial consortium achieved 29.8 and 43.4% removal under the same conditions. The consortium at 30 °C showed the most favorable combination of COD removal and electrical response, whereas S. acutus at 30 °C reached the highest maximum voltage and stored energy, although with greater signal variability. The CH4, H2, and CO2 signals differed among conditions and were consistent with the possible participation of fermentative and methanogenic processes alongside electrogenic activity, although gas production rates and the contribution of individual pathways were not quantified. Overall, the results demonstrate the operational feasibility of the proposed MFC for coupling wastewater treatment with a measurable electrical response and support further evaluation of native microbial consortia as anodic biocatalysts.