Enhancement of Biohydrogen Yield by Co-digestion of Waste Glycerol and Glucose

AbstractBiological hydrogen production from glycerol waste with glucose as co-substrate was tested in batch reactor at the varying mass ratios of glycerol and glucose. All ratios have equivalent extent of total chemical oxygen demand of 9.13 g L-1.COD. Fermentation was setup in 0.5 L glass bottle, 37o C, and pH 6. Liquid and gas samples were collected to analyze concentrations of volatile fatty acids and glycerol; and gas compositions. The results showed that glycerol/glucose ratio plays an important role on the H2 yield. Maximum H2 yield was obtained at the glycerol/glucose ratio of 75:1. Acetate and butyrate were the main fermentative end products. This work demonstrated glucose can be used as a co-substrate to promote the H2 yield in the fermentation of waste glycerol