Work

Efficient fractionation of Chinese fir lignocellulose using acidified deep eutectic solvent with downstream valorization into value-added cellulosic nanofillers and propylguaiacol

Year: 2025

Type: article

Abstract: Fractionation of softwood lignocellulose poses challenges due to its relatively high lignin content and complex interlinkages. In this study, an acidified deep eutectic solvent (choline chloride/ethylene glycol with 1 wt% AlCl₃) was employed to effectively fractionate Chinese fir chips into cellulose-rich and lignin fractions, achieving good to excellent yields. The cellulose-rich fraction was directly valorized into lignin-containing cellulose nanofibers (LCNFs) with a high yield. The prepared LCNFs were utilized as functional nanofillers in waterborne polyurethane wood coatings (WWC), resulting in an increase in tensile strength from 15.2 ± 0.35 MPa to 18.5 ± 0.43 MPa with the optimal addition of 0.5 wt% LCNFs. Furthermore, the addition of LCNFs significantly improved the coating properties, including hardness and wear resistance. The remaining lignin in the LCNFs imparted excellent optical properties to the WWC film, imparting a warm amber hue and improved texture convexity after coating. Analysis of the lignin fractions revealed a high total content of β-O-4 linkages. Following a catalytic hydrogen transfer depolymerization process, 9.8 wt% of propylguaiacol was obtained with near-quantitative selectivity. This study highlights the effectiveness of acidified deep eutectic solvents in the refinery of softwood lignocellulose, providing a novel pathway for the production of value-added bio-based nanomaterials and chemicals. • An acidified DES fractionated Chinese fir lignocellulose with high efficiency. • Integrated DES-based fractionation and valorization to produce valuable nanomaterials and bio-chemicals. • Cellulose-rich fraction was transformed into cellulosic nanofillers for waterborne coating. • The lignin fraction was catalytically depolymerized to ∼10 wt% yield propylguaiacol with excellent selectivity.

Source: Industrial Crops and Products

DOI: 10.1016/j.indcrop.2025.120916