Efficient conversion of cellulose to furfural with carbon-based solid acid catalyst in pure GVL

Abstract

The valorization of cellulose in lignocellulose into high-value products is a crucial step in biorefinery processes. In this study, FeCl₃·6H₂O was impregnated and supported on a carbon-based substrate, followed by carbonization and sulfonation to prepare the composite carbon-based solid acid. The resulting composite carbon-based solid acid was used as the catalyst, while γ-valerolactone, a lactone solvent, served as the reaction medium for producing furfural as the product from cellulose. When using this catalytic system to treat cellulose, under appropriate reaction temperature and residence time, the yield of furfural reached 75.26%, while the conversion rate of cellulose was 99.8%. Characterization techniques including SEM, EDS, XRD, XPS, and Py-FTIR were employed to confirm that the composite carbon-based solid acid possessed Brønsted acid sites, Lewis acid sites, and -Cl active groups, all of which exhibited excellent catalytic activity and selectivity towards furfural production. Furthermore, the synergistic effect between the catalytic activity of the three active groups in the carbon-based solid acid and the inhibitory effect of the nonpolar solvent on side reactions contributed to the outstanding performance of the catalytic system. And this study proposes a possible reaction pathway for the conversion of cellulose to furfural. This research provides an efficient pathway for the valorization of cellulose and holds significance in furfural production and biomass conversion.

Graphical abstract