Energy recovery through biohydrogen production for sustainable anaerobic waste treatment: An overview

The paper is a comprehensive review of the literature for the last five years to provide the current status of H2 production through anaerobic digestion of industrial waste. Hydrogen production through dark fermentation is still far from industrial application. More research is needed to overcome the metabolic limitation and increase H2 yield, rate, and substrate-to-H2 conversion efficiency in a stable process. Generally, studies on effects of culture pretreatment are contradictory and lacked energy and cost analysis in their evaluation. More studies are expected to appear on two-stage and integrative systems of various H2 and other biofuels or value-added chemicals bioprocesses. Metabolic modelling, metabolic engineering, and molecular biology aspects of the microbial community are the current research areas for H2 production through dark fermentation and a coordinative research agenda is required to integrate them into a goal-directed plan. Investment and funding of research are the major drives needed to achieve a milestone.