Methane-fueled microbial fuel cells with the formate-acclimating electroactive culture

Abstract

Methane gas is widespread in natural environments and anaerobic wastewater treatment sites, bringing the risk of the greenhouse effect and energy loss if left unmanaged. A methane-fueled microbial fuel cell (MFC) can convert methane to electricity under mild condition, but faced difficulties in startup. In this study, the new startup strategy and operation performance for methane-fueled MFCs were investigated. After the pre-cultivation of formate-acclimating electroactive culture, the methane-fueled MFC was successfully started up in a short time of 53 d. Increasing concentrations of molybdenum and tungsten in medium facilitated both methane consumption and electricity generation. Under the optimal condition (batch duration of 11 h, 30 °C, pH 7 buffered by phosphate buffer solution), the methane-fueled MFC achieved the maximum power density of 166 mW/m3, a coulomb production of 6.58 ± 0.07C/batch, a CE of 27.4 ± 0.4% and a methane consumption of 31.2 ± 0.3 μmol/batch. This work explored a suitable inoculum (formate-acclimating electroactive culture) for methane-fueled MFCs.