Biohydrogen Production in Substrates Combination of Vinasse and Tofu Whey Using Photosynthetic Bacteria Rhodobium marinum

Hydrogen gas is generated by the fossil fuel refinery process, fixation of sunlight, wind turbine, and water electrolysis. Hydrogen gas is promising energy due to its high energy content and clean combustion. It is also able to be produced by fermentation series, using waste as a substrate. Vinasse is a waste of ethanol distillation from fermented molasses, which still has high Chemical Oxygen Demand (COD) content. The COD is mainly composed of many organic loads that potential to produce hydrogen. Tofu whey (TW), which still has high nitrogen content, is waste generated from the tofu production process. TW is reported to contain high of valuable nutrients, including protein that contains nitrogen. The combination of both liquid wastes is a suitable substrate for hydrogen gas production using Rhodobium marinum . This work aimed to study hydrogen gas, Hydrogen Production Rate, and COD Removal Rate of hydrogen production using a combination of both liquid wastes. Biohydrogen production was examined by varying COD of vinasse/Nitrogen from TW (10,000/1-50,000/1) at a particular fermentation time in the 3 rd , 6 th, and 9 th days. The highest hydrogen gas and Hydrogen Production Rate (HPR) was obtained at substrate concentration 40,000/1 on 9 th day of fermentation, namely 95.72±6.51 mL H 2 /L and 121.44 mL H 2 /L/d, respectively. COD removal and COD Removal Rate were 7820±400.69 mg COD/L and 799.77 mg COD/L/d. Thus, it can be concluded that the combination of Vinasse and TW has potential as a substrate to biohydrogen production using Rhodobium marinum .