AbstractIn this study, the influence of alkaline hydrogen peroxide (H2O2) pretreatment of the three different plant sources: Miscanthus giganteus, Sorghum Moench, and Sida hermaphrodita, for biogas production was investigated. The influence of temperature, reaction time, and H2O2 concentration on the efficiency of biomass degradation and on the further methanogenic fermentation were studied. The results obtained after chemical pretreatment indicate that using H2O2 at alkaline conditions leads to the decomposition of three major structures: lignin, hemicellulose, and cellulose. The best results were achieved for the process performed at 25°C for 24 h with the use of a 5 mass % H2O2 solution. Although the degradation level was very high for all three plant sources, the biogas production from the energy crops pretreated chemically was strongly inhibited by byproducts and the residual oxygen formed after H2O2 decomposition. This fact indicates that alkaline H2O2 pretreatment is a very promising method for plant material degradation for further biogas production, but pretreated biomass must be separated from supernatant before the fermentation process because of the high concentration of inhibitors in the hydrolysates. The best results were obtained for Sida with biogas and methane production of 2.29 Ndm3 and 1.06 Ndm3, respectively.
Kinetics of Diauxic Biogas Production from Energy Crops: Sunflower (Helianthus annus) and Napier Grass (Pennisetum purpureum) with Animal Manure