One-vessel synthesis of 5-hydroxymethylfurfural in concentrated zinc chloride solution from lignocellulosic materials

Abstract

The synthesis of bio-based chemicals, such as 5-hydroxymethylfurfural (HMF) and its derivatives, from cellulosic biomass resources has been attempted for years. However, the harsh reaction condition, toxicity of the catalysts applied, and low efficiency of the conversion process have deterred its industrial implementation. Herein, the authors investigated the degradation and conversion of cellulose into HMF in a concentrated zinc chloride solution. The effects of reaction conditions and co-catalysts on the conversion were evaluated. A 69.5% HMF yield from cellulose was obtained in the condition of 1 h and 150 °C using 0.2 mol·L-1 of HCl without co-catalyst during the conversion. Moreover, the ZnCl2 aqueous solution displayed good reusability. Finally, a simplified kinetic model of the conversion of cellulose to HMF in a concentrated zinc chloride solution was developed, and the reaction kinetics were investigated.

A high curing efficiency sucrose-based adhesive via two-step modification by toluene-4-sulfonic acid and methylenediphenyl diisocyanate

“…Compared with the inorganic acid catalysis method, organic acid catalytic conditions are milder, and some organic acids can be pyrolyzed into non-toxic molecules including CO 2 , formic acid, and fumaric acid (Chen et al, 2017;Zhang et al, 2015). Additionally, metal ions can be used as catalysts to improve the yield of 5-HMF, such as Al 3+ (Nie et al, 2020;Zuo et al, 2022), and Zn 2+ (Zhang et al, 2017;Zheng et al, 2010). Therefore, medium strength inorganic acid phosphoric acid (H 3 PO 4 ), strong organic acid toluene-4-sulfonic acid (TsOH), aluminum trichloride (AlCl 3 ), zinc chloride (ZnCl 2 ), and ammonium chloride (NH 4 Cl) were tested as catalysts for sucrose-based solution (SS) synthesis.…”