Construção e operação de uma célula combustível microbiana com análise de bactérias eletroativas

Abstract

In recent years, bioelectrochemical systems have gained prominence due to increasing concerns about water scarcity. Particularly, microbial fuel cells (MFCs) have shown their potential to convert the chemical energy present in organic compounds into electricity through catalytic processes mediated by microorganisms. In addition to promising renewable electricity generation, these systems play a fundamental role in removing organic compounds from wastewater, characterized by their low energy and w ater consumption, self sustainable biocatalysts, high conversion efficiency, and reduced costs. Where developed and evaluated MFC (Microbial Fuel Cell) bioelectrochemical systems Microbial fuel cell, in addition to obtaining data on the performance of el ectroactive bacteria in Fortaleza/CE. Experimental results demonstrated that MFCs operated in batch mode for 144 days (MFC1) and 125 days (MFC2) produced maxima of ~500 mV, with batch cycle times varying around 2 days. A significant increase in microbial g rowth was observed in MFC1 and MFC2, along with cell stabilization. The data also revealed variations in pH, temperature, and conductivity settings throughout the experiment. This finding is particularly promising as it indicates that the production of 550 mV voltage is linked to a variety of bacteria, differing significantly from various studies focusing on Geobacter and Shewanella as the main protagonists in microbial fuel cells. Therefore, in this study, the predominant genera were Camamonas, Serratia, Paraclostridium, Bacillus, and Clostridium . It is noteworthy that MFC1 achieved a production of 600 ± 0.2 mW/m², while MFC2 recorded 350 ± 0.5 mW/m². These results indicate an association of the 550mV voltage production with a variety of bacteria, expanding the understanding of the protagonists in microbial fuel cells. It is concluded that the development of MFC technology should not be based solely on pure cultures but also on mixed cultures, which have proven to be effective and robust. These findings open up new possibilities to explore the potential of different bacterial genera in the efficiency and functional diversity of these technologies.