Tuesday, April 30, 2013
Exhibit Hall
Lignocellulose represents a key sustainable source of biomass for transformation into biofuels and bio-based products. Effective pretreatment strategies are needed to lower the high processing cost without degrading the key components of lignocellulose. Ionic liquids (ILs) have been shown to be excellent solvents for the pretreatment/dissolution of biomass. The dissolved biomass can be regenerated, with the addition of an anti-solvent, for further hydrolysis to glucose. The primary focus of this work is to assess the potential agave bagasse (AGB-byproduct of tequila industry) as a potential candidate for biofuel feedstock and to identify the most important factors affecting its digestibility. Switchgrass (SWG) was used as a control to measure the effectiveness of AGB as bioenergy candidate. The IL pretreatment was conducted using 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) at 120°C and 160°C for 3 h and 15 % biomass loading. The regenerated biomass was subjected to two different saccharification schemes. Pretreated materials were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and wet-chemistry techniques. Pretreated SWG and AGB samples had decreased lignin content and high saccharification yield. While pretreatment using [C2mim][OAc] was very effective in improving the digestibility of both feedstock. IL pretreatment at 160 °C resulted in higher delignification for AGB (45.5%) than for SWG (38.4%) when compared to 120 °C (AGB-16.6%, SWG-8.2%), formation of a highly amorphous cellulose structure and a significant enhancement of enzyme kinetics. These results highlight the potential of AGB as a biofuel feedstock that can produce high sugar yields with IL pretreatment.