Production and recovery system for furan compounds from rice straw using an ionic liquid (1-methylimidazolium hydrogen sulfate) and vacuum steam distillation

Abstract

Furan compounds, including 5-hydroxymethylfurfural and furfural, can be synthesized from biomass and have garnered attention for their potential applications in biofuels and resin precursors. In this study, the synthesis of the furan compounds from rice straw was explored using a combined approach of ionic liquid treatment, specifically 1-methylimidazolium hydrogen sulfate ([MIM]HSO4), and vacuum steam distillation. Through the optimization of various processing parameters, we established that the best conditions for the furan compound production include: a cold trap cooling temperature of – 196 ℃, a system pressure of 10 hPa, a treatment temperature of 180 ℃, a reaction duration of 30 min, a sample loading of 1wt%, and a particle size range of 45–90 µm. Under these conditions, the resultant yield of the furan compounds was quantified at 27.9wt%. Additionally, the recyclability of the utilized ionic liquid was evaluated. Notably, even after four recycling cycles (encompassing a total of five reactions), the yield of the furan compounds remained consistent, underscoring the viability of ionic liquid reuse.