Location: Wheat, Sorghum and Forage ResearchTitle: Monitoring and Analyzing Process Streams Towards Understanding Ionic Liquid Pretreatment of Switchgrass (Panicum virgatum L.)) Author
Submitted to: BioEnergy Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/4/2010
Publication Date: 5/14/2010
Publication URL: http://hdl.handle.net/10113/44307
Citation: Arora, Rohit, Manisseri, Chithra, Li, Chenlin, Ong, Marcus, Scheller, Henrik Vibe, Vogel, Kenneth, Simmons, B.A., Singh, Seema. 2010. Monitoring and Analyzing Process Streams Towards Understanding Ionic Liquid Pretreatment of Switchgrass (Panicum virgatum L.). BioEnergy Research. 3:134-145. Interpretive Summary: Biomass from plants such as switchgrass will require pretreatment to improve the efficiency and total liquid fuel production from biomass in a biorefinery. Ionic liquids, which are salts in a liquid state, were previously demonstrated to improve conversion efficiency when used to pre-treat switchgrass biomass. In this study the effect of temperature and treatment time on ionic liquid pretreatment of switchgrass biomass was evaluated. Effect of pretreatment temperature and duration were both important but their effect varied on hemicelluloses and celluloses. Additional research will be needed to optimize pretreatment procedures using ionic liquids.
Technical Abstract: Fundamental understanding of biomass pretreatment and its influence on sacchrification kinetics, total sugar yield, and inhibitor formation is essential to develop efficient next-generation biofuels strategies, capable of displacing fossil fuels at a commercial level. In this study we investigate the effect of residence time and temperature during ionic liquid (IL) pretreatment of switchgrass using 1-ethyl-3-methyl imidazolium acetate. The primary metrics of pretreatment performance are biomass delignification, xylan and glucan depolymerization, porosity, surface area, cellulase kinetics, and sugar yields. Compositional analysis and quantification of process streams of saccharides and lignin demonstrate that delignification increases as a function of pretreatment temperature and is hypothesized to be correlated with the apparent glass transition temperature of lignin. IL pretreatment did not generate monosaccharides from hemicelluloses. Compared to untreated switchgrass BET surface area of pretreated switchgrass increased by a factor of ~40. There is an observed dependence of cellulose kinetics with delignification efficiency. Although complete biomass dissolution is observed after 3 h or IL pretreatment, the pattern of sugar release, saccharification kinetics and total sugar yields are strongly correlated with temperature.