Valorization of wheat straw to furfural and glucose via ZnCl2/gamma-valerolactone system

Abstract

The development of efficient catalytic routes to platform molecules from lignocellulosic biomass represents a critical objective for establishing sustainable chemical industries. Here, we present an innovative cascade catalysis approach for the conversion of wheat straw into furfural (FAL) and glucose within a molten salt hydrate/γ-valerolactone (MSH/GVL) system. MSH composition critically governed wheat straw fractionation efficiency and product distribution. The ZnCl₂·60 wt%/GVL (1 : 1, v/v) system demonstrated exceptional performance, preserving 98.5% cellulose while removing 93.5% hemicellulose and 71.2% lignin at 140 °C for 40 min. Importantly, GVL suppressed condensation of hemicellulose-derived intermediates, enabling a direct 67.3% FAL yield from wheat straw. Furthermore, the cellulose-enriched residue underwent selective chemocatalytic hydrolysis in an acidified ZnCl₂·65 wt% system at 80 °C for 20 min, affording glucose in 93.8% yield. This work establishes an integrated catalytic strategy for the valorization of lignocellulosic biomass into key platform molecules, providing a promising route for sustainable biorefining.