Advancing two-stage hydrogen production from corn stover via dark fermentation: Contributions of thermally modified maifanite to microbial proliferation and pH self-regulation

Abstract

This study introduces a two-stage hydrogen production enhancement mechanism using natural particle additives, with a focus on the effects of thermally modified maifanite (TMM) and pH self-regulation on dark fermentation (DF). Initial single-factor experiments identified preliminary parameters for the addition of TMM, which were further optimized using a Box-Behnken design. The established optimal conditions which include mass of 5.5 g, particle size of 120 mesh, and temperature of 324 °C, resulted in a 28.7 % increase in cumulative hydrogen yield (CHY). During the primary hydrogen production stage, TMM significantly boosted the growth and activity of Clostridium_sensu_stricto_1, enhancing hydrogen output. Additionally, a pH self-regulating phenomenon was observed, capable of initiating secondary hydrogen production and further augmenting CHY. These findings presented a novel and efficient approach for optimizing biohydrogen production, offering significant implications for future research and application in sustainable energy technologies.