Sunday, August 11, 2013
Pavilion (Sheraton San Diego)
Ethanol produced from lignocellulosic biomass is a promising renewable alternative to diminishing oil and gas liquid fuels. Sugarcane is already an important industry in South Louisiana, and the cultivation of “energy cane” varieties as a fuel source has great potential to bolster this industry for years to come. Lignocellulosic biomass consists of sugars, hemicellulose and cellulose, bound in a matrix by lignin. The process of converting these sugars into usable fuel ethanol requires a pretreatment to remove the lignin, thus making fermentation via recombinant Escherichia coli possible. Determining optimal pretreatment techniques for fermentation is essential for the success of lignocellulosic energy production. The purpose of this study was to evaluate energy cane for ethanol production using different pretreatment techniques. These methods included using acid hydrolysis and solid-state fungal pretreatments with white rot and brown rot fungi to remove lignin before enzymatic saccharification and fermentation. The results revealed that all pretreatment processes produced ethanol; however, the highest yield of 3000mg/L was produced using a dilute acid hydrolysis of 3% sulfuric acid. Furthermore, fungal pretreatment followed by acid hydrolysis reduced the acid requirement from 3% to 1% sulfuric acid solution while still producing 3000mg/L of ethanol. This combined fungal and acid pretreatment will significantly reduce the cost of producing fuel grade ethanol when used in a large-scale production system, making this method one step closer to competing with other sources of fuel grade ethanol.