Hydrogen production in batch culture of mixed bacteria with sucrose under different iron concentrations

Abstract

The effect of the iron concentration on hydrogen yield was investigated in batch tests by heat-shocked mixed cultures growing on a sucrose mineral medium at 35 °C. The hydrogen production yield increased obviously with increasing iron concentration from 0 to 1600 mg FeSO 4 l - 1 , and then slightly decreased when the iron concentration increased from 1600 to 5000 mg FeSO 4 l - 1 . The maximum amount of hydrogen production (2.73 mol/mol sucrose) was obtained at the iron concentration of 1600 mg FeSO 4 l - 1 . The hydrogen production yield and the butyric acid/acetic acid ratio followed a similar trend, suggesting that the formation of butyrate seems to favor hydrogen production.