Sustainable production of 5-hydroxymethylfurfural from fructose and inulin using active and stable acidic ionic liquids as homogeneous and heterogeneous catalysts

MENDEZ LETICIA,; CANEPA ALICIA; ROMANELLI GUSTAVO P.; CASELLA, MÓNICA L.; ILEANA DANIELA LICK

Sustainable Chemistry and Pharmacy

Elsevier B.V.

Año: 2024 vol. 39

Two Brønsted acidic ionic liquids (IL) were synthesized by quaternization of an organic base (imidazole and triethylammonium) with 1,4-butane sultone and its successive protonation with sulfuric acid. After a deep characterization, they were tested, as catalyst and solvent, in the 5-hydroxymethylfurfural production from D-fructose. IL1, [C4SO3Hmim][HSO4], showed the best catalytic activity in the dehydration of fructose, obtaining 58% of 5-HMF. This IL could be recycled and reused without appreciable loss of catalytic activity in four catalytic cycles (58%, 57%, 56%, and 53%, respectively). It was used with other carbohydrates (monosaccharides, disaccharides, and polysaccharides) showing that all substrates containing fructose units were efficiently converted to 5-HMF. Furthermore, a heterogeneous system was prepared with IL1 supported on silica gel, and this system exhibited high activity in the fructose dehydration reaction and a yield of 70% of isolated and purified 5-HMF was achieved.