Wednesday, May 4, 2011: 8:30 AM
Grand Ballroom B, 2nd fl (Sheraton Seattle)
Levulinic acid and furfural have been identified as leading reactive intermediates to make from cellulosic biomass for conversion to a wide range of products including drop-in hydrocarbon fuels. However, furfural yields by dilute acid pretreatment of cellulosic biomass are limited in aqueous solutions due to its polymerization. Reaction of xylose in the presence of organic solvents (e.g., methyl isobutyl ketone (MIBK) and tetrahydrofuran (THF)) enhanced yields by reducing the amount of furfural in water that can react further. In this study, various reaction conditions, acid catalysts, and solvents were applied in a three phase system for dilute acid hydrolysis of hemicellulose to xylose followed by dehydration of that xylose to furfural in water and solvent extraction of furfural. Yields were compared to conventional furfural production from cellulosic biomass and xylose production followed by reaction to furfural with and without solvents, and furfural yields from the three phase system were found to be significantly higher. The cellulose enriched solid residue left in the aqueous phase after solvent removal was broken down to glucose by enzymatic hydrolysis or 5-HMF by acid catalyzed hydrolysis and dehydration. We also applied a novel single step process developed in our lab for acid catalyzed hydrolysis of the residual cellulose to HMF followed by further dehydration to levulinic acid. Conditions were identified to maximize yields of target products from each of these approaches. Reaction pathways for levulinic acid and furfural production and conversion to jet fuel were also identified.