Highly efficient, rapid, and practical conversion of carbohydrate into 5-hydroxymethylfurfural using a continuous-flow reactor with 1-(4-sulfobutyl)-3-methylimidazolium bromide ionic liquid as a catalyst.

[Display omitted] • The flow reactor was employed for fructose dehydration to 5-HMF using acidic ionic liquids. • 1-(4-Sulfobutyl)-3-methylimidazolium bromide resulted in the maximum 5-HMF yield, which was achieved in 68.0% for 5 min. • The method showed environmentally friendly and practical synthesis of HMF. The application of continuous flow reactors for sustainable chemical research and production has attracted much attention. 5-Hydroxymethylfurfural (5-HMF) has been considered high potential for the production of chemicals and fuels. This work demonstrated the promise of synthesizing 5-HMF with high yield and selectivity using ionic liquids under continuous flow. The effects of temperature, solvent, catalyst activity, catalyst loading, substrate, and large-scale synthesis were investigated to choose the optimal reaction condition. As a result, 1-(4-sulfobutyl)-3-methylimidazolium bromide afforded 5-HMF in the good yield, about 68% in DMSO at 140 °C for 5 min. This approach is not only an eco-friendly pathway but also saves time, which can obtain high efficiency and apply in the large-scale production of 5-HMF from fructose. [ABSTRACT FROM AUTHOR]