Efficient synthesis of 5-ethoxymethylfurfural from biomass-derived 5-hydroxymethylfurfural over sulfonated organic polymer catalyst

Herein, we investigated catalytic potential of a functionalized porous organic polymer bearing sulfonic acid groups (PDVTA-SO(3)H) to the etherification of 5-hydroxymethylfurfural (HMF) to 5-ethoxymethylfurfural (EMF) under solvent-free conditions. The PDVTA-SO(3)H material was synthesized via post-synthetic sulfonation of the porous co-polymer poly-divinylbenzene-co-triallylamine by chlorosulfonic acid. The physicochemical properties of the PDVTA-SO(3)H were characterized by FT-IR, SEM, TG-DTG, and N(2) adsorption isotherm techniques. PDVTA-SO(3)H had high specific surface area (591 m(2) g(−1)) and high density of –SO(3)H group (2.1 mmol g(−1)). The reaction conditions were optimized via Box–Behnken response surface methodology. Under the optimized conditions, the PDVTA-SO(3)H catalyst exhibited efficient catalytic activity with 99.8% HMF conversion and 87.5% EMF yield within 30 min at 110 °C. The used PDVTA-SO(3)H catalyst was readily recovered by filtration and remained active in recycle runs.