Performance evaluation of a single-chamber microbial fuel cell with Zygosaccharomyces bailii

Abstract

A microbial fuel cell (MFC) uses electroactive microorganisms, usually bacteria, to provide electrical energy while treating wastewater. The yeast-based MFCs are gaining relevance since yeasts present a higher ability to grow in harsh environments than most bacteria. Zygosaccharomyces bailii was used in an MFC to treat a synthetic winery wastewater, operating in sequential batch mod. The effect of yeast inoculum medium, pH, anodic conditions and the cathode current collector characteristics (configuration and material) on the system performance was evaluated, through polarisation measurements. A maximum power density of 1.34 ± 0.01 mW/m2 was achieved under anaerobic conditions, a synthetic winery wastewater with a pH of 7, and a cathode current collector made of titanium with an open ratio of 41 %. The wastewater treatment efficiency ranged between 27 % and 35 %. This study highlighted how alterations in the MFC characteristics can minimise these systems limitations, leading to improved performances. Moreover, the present work is an important step in yeast-based MFCs applied to wastewater treatment.