This project is to fundamentally understand an innovative process (HDA: hydrolysis- dehydration-aldol condensation) for producing ?drop-in? biofuel from lignocellulosic biomass. The process directly converts cellulose and hemicellulose in the biomass to furan-based precursors for fuel-grade hydrocarbons in one step under mild conditions (120-140°C) without prior biomass pretreatment and fractionation. The precursors can be easily converted to fuel- grade hydrocarbons via hydrogenation/dehydration. Specifically, in the presence of acetone as solvent and reactant and halide salt (such as lithium bromide) and mineral acid as catalysts, the biomass undergoes hydrolysis of cellulose and hemicellulose to monosaccharides, dehydration of the monosaccharides to furfural and hydroxymethylfurfural (HMF), and aldol-condensation of HMF and furfural with acetone, and ends up with the formation of furan-based precursors with chain length of C6?C21. Meanwhile, lignin in the biomass is extracted with high purity, low molecular weight, and good reactivity, showing great potential in lignin co-products development. The unreacted acetone and catalysts can be recycled and reused.
The specific objectives of this project are (1) to further optimize the HDA process to improve the conversion yield and selectivity of the furan-based oxygenate precursors and to establish process mass balance; (2) to elucidate the reaction pathways of cell-wall components (cellulose and hemicellulose) and to fundamentally understand the HDA process; (3) to characterize chemical, physical and thermal properties of the extracted HDA lignin.
In addition to innovative research activities, this project also emphasizes on high-quality education, development and dissemination of new knowledge, and outreach activities. The success of proposed process would provide an alternative and innovative approach for producing drop-in liquid fuel from lignocellulosic biomass, such as agricultural crop residues (corn stover), energy crop (switchgrass), and forest biomass (wood). The integrated education plan will target broad range of students. In addition to regular undergraduate and graduate students, special attention will be paid to the students from high school and underrepresented groups by encouraging them participating summer projects on bioenergy.
