Precursor Production of Sustainable Aviation Fuel from γ-Valerolactone-Deconstructed Biomass Coupled with Thermal Conversion

Abstract

Sustainable aviation fuels (SAFs) are mainly composed of cycloalkanes, paraffins, and aromatics, representing an inevitable alternative to conventional fossil fuels. Alcohols and phenolic compounds act as critical precursors to produce branched alkanes and cycloalkanes, the major constituents of sustainable aviation fuel. Biomass is primarily composed of C6 sugar, and aromatic structures, which can be employed for the production of phenolics and alcohols. However, the direct thermal conversion of biomass results in poor selectivity toward phenolic and alcoholic products. Based on the structural characteristics of three typical biomass feedstocks, γ-valerolactone (GVL) pretreatment of biomass coupled with thermal conversion to produce phenolics and alcohols was proposed. The results showed that GVL pretreatment could effectively decompose corncob, poplar, and pine into cellulose-rich fractions (C6-based structures) and lignin-rich fractions (aromatic structures). The highest ethanol yield of 24.4 wt % was obtained by the catalytic hydrogenolysis of the corncob-based cellulose-rich fraction over the Ni@C catalyst. The highest relative content (54.1%) of phenols from fast pyrolysis of lignin-rich fractions extracted from poplar was achieved. This work demonstrates an advanced process to achieve a directional conversion of biomass to precursor production of SAFs.