Tuesday, May 1, 2012: 2:00 PM
Napoleon Ballroom A and B, 3rd fl (Sheraton New Orleans)
Sweet sorghum bagasse obtained from advanced solid-state fermentation (ASSF) process, is a potential feedstock for cellulosic ethanol production due to its abundant cellulose content and low collection cost. Various pretreatment methods were optimized to break its recalcitrant structure in present study. They were dilute sulfuric acid, alkaline (NaOH) and liquid hot water technologies. The corresponding results of enzymatic hydrolysis were shown the sweet sorghum bagasse pretreatment with liquid hot water had the highest glucan conversation rate about of 100 % at 5 % solid loading. In order to investigate the physical and chemical structural changes of substrates, the chemical compositions, cellulose degree of polymerization, lignin substructure were determined. The results showed the substrates pretreated by alkaline has the lowest lignin content and the highest hemicellulose content, whereas the cellulose degree of polymerization of substrates more significantly by dilute acid and liquid hot water than by alkaline pretreatment. The crystallinity index of cellulose was also decreased by pretreatment technology. The Low pH pretreatments effected the biomass crystallinity much more than higher pH method. The characterization of lignin substructure was suggested the content of p-hydroxyphenyl (H) in lignin was decreased obviously by dilute acid and liquid hot water technologies, moreover, less amount of H unit in lignin more of the amounts of glucose released from the substrates.