Optimization of fructose dehydration to 5-hydroxymethylfurfural catalyzed by SO3H-bearing lignin-derived ordered mesoporous carbon

A sulfonated lignin-derived mesoporous carbon (LDMC-SO 3 H) was prepared from kraft lignin (KL) using phenolation and soft-template method followed by sulfonation. LDMC-SO 3 H bearing a sulfonic acid density of 0.65 mmol/g possessed a well-ordered 2D hexagonal mesoporous characteristics with mesopore volume of 0.067 cm 3 /g and specific surface area of 262 m 2 /g as well as mesopore size of 3.42 nm. A high 5-hydroxymethylfurfural (5-HMF) yield of 98.0% with a full fructose conversion was obtained using LDMC-SO 3 H as catalyst under the optimized reaction conditions of reaction temperature and time of 140 °C and 120 min, initial fructose concentration of 100 g/L, catalyst load of 0.1 mg/mg in DMSO. Furthermore, there was no obvious decrease in 5-HMF yield (≥95.0%) within the five-cycle experiment, highlighting the superior reusability and stability of LDMC-SO 3 H in fructose-to-5-HMF transformation.