Compressed hot water pretreatment enhanced bioethanol production from corn stalk

Finding alternative use for corn stalk (CS), an abundant agricultural waste, in energy production would solve the problem of it becoming environmental encumbrance and increases energy availability. CS used in this study was exposed to compressed hot water (CHW) pretreatment at 100, 120, 140, 160, 180 and 200 °C for reaction time 10 min and the slurry was used for production of ethanol in a simple bioreactor kept at 30 °C. Optimal performance was recorded with the 180 °C pretreated corn stalk (PCS). Filtration of the slurry improved ethanol production to 31.06 g/L. Under optimal conditions, 73.8% degradation of hemicellulose was recorded. Scanning Electron Microscope images showed induced porosity and increased surface area in the PCS. Crystallinity index of the PCS increased as revealed by X-ray diffraction analysis. CHW pretreatment shows potential as a promising pretreatment method for lignocellulosic materials use for large-scale production of bioethanol that is useable as fuel.