Lime Pretreatment of Coastal Bermudagrass for Bioethanol Production

摘要

The steady increase of energy consumption along with current dependence on crude oil to satisfy energy demands, calls for renewable energy sources development all over the world. Coastal bermudagrass is regarded as a potential lignocellulosic feedstock for bioethanol production in the southeast of the United States. Lime pretreatments of coastal bermudagrass for enhanced reducing sugars recovery was investigated in this study which examined a variety of temperatures (room temperature to 121°C) at arange of residence times with different lime loadings (0.02 to 0.20 g/g dry biomass). Total lignin reduction after pretreatment, and total reducing sugars production along with glucose and xylose yields after enzymatic hydrolysis were analyzed. During pretreatment, 10-20% of lignin was removed. After enzymatic hydrolysis with excessive cellulases and cellobiase, the best total reducing sugars yield for lime pretreatment was 78% of the theoretical maximum which is over two times that of untreated biomass. The recommended condition is 100°C for 15 min with a lime loading of 0.1 g/g dry biomass under which 87% of glucan and 68% of xylan were converted to glucose and xylose respectively.