Unearthing the potential of organic biowastes via microbial fermentation for production of CH₄ and H₂ / biohythane

The growing reliance on fossil fuels for global energy needs, particularly in transportation, has resulted in significant environmental harm, including the degradation of air quality and ecosystems. This has intensified the urgency to transition toward renewable energy sources. Among the alternatives, biomass-derived fuels present a viable solution. By utilizing sustainable biomass and organic waste, biofuels like hydrogen and methane can be produced through microbial processes. However, optimizing these processes requires advanced microbial systems and fine-tuned operational parameters. Waste biomass, in particular, holds promise as a feedstock for generating biofuels that can address both current and future energy demands while preserving environmental health. This article focuses on the development of biohythane, a hybrid biofuel produced by combining biohydrogen and biomethane production processes. By integrating these processes at both the bioprocess and reactor levels, biohythane emerges as a new, sustainable fuel option with potential applications in transportation. Researchers are actively exploring ways to merge the traditionally separate production pathways of biohydrogen and biomethane into a single, efficient bioprocess. Several approaches, including two-stage fermentation (dark fermentation followed by methanogenesis), have shown promise in generating biohythane from waste biomass. Moreover, the potential of newly engineered microbial systems to enhance production efficiency is discussed. This paper provides a comprehensive overview of biohythane production, examining the various waste resources that can be utilized, the hydrolysis techniques involved, and the bioprocesses that lead to the synthesis of this promising biofuel.