Co-fermentation of residual algal biomass and glucose under the influence of FeO nanoparticles to enhance biohydrogen production under dark mode.

The present study reports FeO nanoparticles (FeO NPs) induced enhanced hydrogen production via co-fermentation of glucose and residual algal biomass (cyanobacteria Lyngbya limnetica). A significant enhancement of dark fermentative H production has been noticed under the influence of co-fermentation of glucose and residual algal biomass using FeO NPs as catalyst. Further, using the optimized ratio of glucose to residual algal biomass (10:4), ∼ 37.14 % higher cumulative H has been recorded in presence of 7.5 mg/L FeO NPs as compared to control at 37 °C. In addition, under the optimum conditions [glucose to residual algal biomass ratio (10:4)] presence of 7.5 mg/L FeO NPs produces ∼ 937 mL/L cumulative H in 168 h at pH 7.5 and at temperature 40 °C. Clostridum butyrium, employed for the dark fermentation yielded ∼ 7.7 g/L dry biomass in 168 h whereas acetate (9.0 g/L) and butyrate (6.2 g/L) have been recorded as the dominating metabolites.