Co-production of hydrogen and electricity from macroalgae by simultaneous dark fermentation and microbial fuel cell

In this study, a hybrid process of dark fermentation (DF) and microbial fuel cell (MFC), sDFMFC, was investigated for simultaneous H2 and electricity production from Saccharina japonica in a single reactor. The sDFMFC exhibited a considerably enhanced energy recovery owing to simultaneous H2/carboxylic acids (CAs) production by DF and electricity production by MFC consuming CAs. The co-production of H2 and electricity was confirmed by a time course of CAs concentration in sDFMFC. An excellent energy recovery of 17.3% was obtained from S. japonica with H2 yield of 110 mL/g-VS and maximum power density of 1.82 W/m2. The sDFMFC showed a diverse microbial community for a desirable microbial conversion of organic substrates. The results indicate that sDFMFC can be a promising single reactor process to produce H2 and electricity from various biomass feedstock with considerable cost savings while ensuring the strength of the individual DF and MFC process.

Automated summary

The study investigated a hybrid process of dark fermentation (DF) and microbial fuel cell (MFC), termed sDFMFC, for simultaneous H2 and electricity production from Saccharina japonica in a single reactor. The results showed that sDFMFC exhibited considerably enhanced energy recovery and confirmed the co-production of H2 and electricity. The process demonstrated a diverse microbial community suitable for microbial conversion of organic substrates.