Work

In-situ control of biohythane production in electro-anaerobic digestion

Year: 2025

Type: article

Abstract: Biohythane, consisting of methane and hydrogen, is a promising clean energy carrier with enhanced combustion properties and reduced greenhouse gas (GHG) emissions. Herein, electro-anaerobic digestion (EAD) was employed as a novel approach for regulating biohythane production. The results revealed that the applied potential significantly influenced biogas production rates and composition. The reactor under 0.1 V (EAD +0.1V ) demonstrated the highest methane yield and the shortest lag period with a final biohythane of 60 % methane and 13 % hydrogen. Meanwhile, improved consumption of volatile fatty acid (VFA) was observed, resulting in a relatively neutral pH. Microbial community analysis showed a substantial increase in hydrogenotrophic methanogens (85 %) and a reduction in acetoclastic methanogens (14 %). The +0.1 V electrode likely acted as an electron sink, enabling electroactive biofilm (EAB) to consume acetate and relieve fermentation bottlenecks and thus sustaining biohythane production. While the exact electron transfer pathway remains uncertain, the present results highlight the potential mechanistic role of electrode-driven acetate consumption in enabling metabolic redirection. Those findings would encourage future efforts to further understand the electron transfer pathways toward the design of scalable EAD systems. • An in-situ single-stage biohythane technology was developed. • Varying applied potentials significantly influence biogas composition, with EAD +0.1V achieving a 13% hydrogen accumulation. • EAD +0.1V shows the increase in hydrogenotrophic methanogens (relative abundance: 85%). • Obvious oxidation current and VFA consumption were observed in EAD_+0.1V group.

Source: Chemical Engineering Journal

DOI: 10.1016/j.cej.2025.170783

Authors: Chao-Chin Chang, Yu-Wen Lin, Chang-Ping Yu, Zhen He

Institutions: Washington University in St. Louis, National Kaohsiung University of Science and Technology, National Taiwan University

Language: English

Topic: Anaerobic Digestion and Biogas Production

Subfield: Building and Construction

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,830