Biohydrogen and Volatile Fatty Acids Production form Food Waste Hydrolysate

Abstract: This work focused a pH readjustment strategy has been applied for the enhancement ofbiohydrogen production form food waste hydrolysate in a semi-pilot scale bioreactor seededwith selectively enriched mixed microbial culture. Different initial pH (pH 6, pH 7, and pH8) was selected for biohydrogen production from FW. When hydrogen production was terminated due to the accumulation of volatile fatty acids in the bioreactor, then the pHof the bioreactor was again readjusted to its initial pH. Highest hydrogen production rate of1.13 L/h (CHP: 58.48 L) was achieved with pH 8 operation which was almost double thanpH 6 and pH 7 operation. Volatile fatty acids (VFA) production was also influenced by thisstrategy. Higher acetic and butyric acids (2471.4mg/L and 947.37mg/L) were observed. Highest buffering capacity (0.1ßmol) significantly contributed towards higher biohydrogenproduction via this pH adjustment strategy. This strategy not only enhanced H 2 productionbut it also increased the waste conversion efficiency towards other biobased productsproduction during acidogenesis of FW.