A novel method for producing hydrogen from water with Fe enhanced by HS− under mild hydrothermal conditions

In this paper, a novel method for producing hydrogen from water with Fe as a reductant promoted by HS− under mild hydrothermal conditions was proposed. Results showed that hydrogen production significantly increased in the presence of HS− compared to that in the absence of HS−. The obvious hydrogen production was achieved in a low reaction temperature of 250 °C and a very short reaction time (less than 2 h). The maximum yield of hydrogen production, which was defined as the percentage of produced hydrogen amount to theoretical one according to completive oxidation of Fe to Fe3O4 to produce hydrogen from water, was 34% at 300 °C. HS− may act as a catalyst and a possible HS−-catalyzed mechanism was proposed. This process may provide a promising solution for biomass-driven hydrogen production from water combined with the process of reducing iron oxide into their zero-valent state by bio-driven chemicals, such as glycerin.