A catalytic biofuel production strategy involving separate conversion of hemicellulose and cellulose using 2-sec-butylphenol (SBP) and lignin-derived (LD) alkylphenol solvents

• A process based on a new alkylphenols (SBP and LD)-based biomass conversion technology is studied.
• New separations for recovery of biomass-derived intermediates (LA and GVL) are developed.
• Separations are integrated with biomass-to-LA, LA-to-GVL, and GVL-to-butene oligomers conversions.
• Proposed strategy is an attractive alternative to catalytic lignocellulosic biofuel.
• Study identifies future research directions in catalytic biofuel production.

A strategy in which the hemicellulose and cellulose fractions of lignocellulosic biomass are converted separately to jet fuel-range liquid hydrocarbon fuels (butene oligomers) through catalytic processes is developed. Dilute sulfuric acid (SA)-catalyzed pretreatment fractionates the first biomass into cellulose and hemicellulose-derived xylose, and these are then converted separately to levulinic acid (LA) using 2-sec-butylphenol (SBP) and lignin-derived (LD) alkylphenol solvents, respectively. LA is upgraded catalytically to butene oligomers via γ-valerolactone (GVL) and butene intermediates. Separation subsystems are designed to recover the alkylphenol solvents and biomass-derived intermediates (LA and GVL) for combination with the catalytic conversion subsystems of hemicellulose, cellulose, and lignin. In addition, a heat exchanger network (HEN) design is presented to satisfy the energy requirements of the integrated process from combustion of biomass residues (degradation products). Finally, a technoeconomic analysis shows that the proposed process ($3.37/gallon of gasoline) is an economically competitive alternative to current biofuel production approaches.