Multiple parameters optimization for maximization of hydrogen production using defined microbial consortia

Abstract

Hydrogen production, using defined microbial consortia, can not only effectively utilize various complex organic wastes to solve the environmental pollution problem but also the energy crisis to some extent. Defined consortia comprising of <i>Enterobacter cloacae</i> IIT BT08, <i>Bacillus coagulans</i> IIT BT S1 and <i>Citrobacter freundii</i> IIT BT L139 in the ratio 2:1:1 was found suitable to utilize molasses (a by-product of sugar industry), and produced 16.66 mole H2/kg COD reduced. Hydrogen yield, using consortia, was found to be more as compared to that obtained from the strains individually. Three physico-chemical parameters namely <i>p</i>H, substrate concentration and temperature were optimized to obtain maximum hydrogen yield. The most suitable experimental conditions for maximum production of hydrogen with respect to substrate concentration, <i>p</i>H and temperature were found to be 16.5 g/L, 7.5 and 35°C, respectively and that of theoretically optimized values were 16.5 g/L, 7.5 and 32.5°C, respectively.