Carbon emissions reduction by catalyzing H ₂ gas harvested from water hyacinth fermentation process using metallic salts

The aim of this study is decreasing the dependence on fossil fuels through introducing an alternative clean energy source in term of H2 gas. Biomass conversion to H2 carried out through the fermentation process. Valorizing H2 production from water hyacinth (WH) can be accomplished by using metallic salts as biocatalysts. Therefore, different salt concentrations ranged from 1.0 to 10.0 g/L were investigated. It was found that the high salinity could produce inhibition effect for hydrogen production. The highest hydrogen yield (HY) of 56.75 ± 0.4 was detected at 3.0 g/L salinity while the lowest HY of 26.12 ± 0.6 was detected at the highest salinity of 10.0 g/L. The nutrients changing and metabolites composition could also be significantly influenced by the salinity. The releasing of carbohydrate from WH could be easily used for hydrogen production, and protein could be accumulated and assimilated during the hydrogen fermentation. The high salinity was harmful to total metabolites (TVFAs) accumulation.