Preparation of 5-hydroxymethylfurfural from fructose and precursors over H-form zeolites

Dehydration of fructose into 5-hydroxymethylfurfural was performed in a batch mode in the presence of H-form zeolites as catalysts, at 165 degrees C and in a solvent mixture consisting of water and methylisobutylketone (1: 5 by volume). Fructose conversion and selectivity to 5-hydroxymethylfurfural were found to depend on both acidic and structural properties of the catalysts used. A maximum in the rate of conversion of fructose was observed for Si/Al ratios of 15 and 11 for H-Y faujasites and H-mordenites, respectively. A maximum in the selectivity to 5-hydroxymethylfurfural was only observed for H-mordenites. The high selectivity obtained (>90-95%) was correlated with the shape selective properties of H-mordenites, and particularly with the absence of cavities within the structure allowing the further formation of secondary products. Fructose precursors such as sucrose, Jerusalem artichoke and inulin were also found to be selectively transformed into 5-hydroxymethylfurfural under the same operating conditions.