Sugar dehydration to 5-hydroxymethylfurfural in mixtures of water/[Bmim]Cl catalyzed by iron sulfateSong, X., Wang, C., Chen, L., Liu, Q., Liu, J., Zhu, Y., Yue, J. & Ma, L., 19-Oct-2020, In : New Journal of Chemistry. 44, 39, p. 16877-16890 14 p.
Research output: Contribution to journal › Article › Academic › peer-review
Ionic liquids (ILs) as an additive was employed in the selective conversion of bio-based carbohydrates to 5-hydroxymethylfurfural (HMF) in this work. The effect of adding various imidazole-based ionic liquids with different anion structures on the production of HMF from fructose was firstly investigated in aqueous media. The presence of 15 wt% of 1-butyl-3-methylimidazole chloride ([Bmim]Cl) ionic liquids in water with Fe2(SO4)3 as the homogeneous catalyst provided a more effective HMF synthesis than that without [Bmim]Cl addition. The enhanced HMF yield was mainly attributed to the fact that [Bmim]Cl might play a vital role in stabilizing the HMF molecule, which could thereby suppress side reactions involving HMF (e.g., its rehydration to levulinic acid or/and polymerization to humins). NMR and FTIR analyses suggested that such stabilization effect stemmed from the interaction of [Bmim]Cl with the hydroxyl and aldehyde groups of HMF through hydrogen bond. By operation in a biphasic system (i.e., with biomass-derived THF solvent as the organic phase and the addition of NaCl salt into water for improving HMF partition), the HMF yield over Fe2(SO4)3 catalyst in the presence of [Bmim]Cl additive could be further improved. The catalyst and ionic liquids were quite stable, which could be reused more than five cycles with a consistent activity. Similar enhancement effect of [Bmim]Cl was also demonstrated in HMF synthesis with better yields from other biomass feedstocks or derivatives (including glucose, sucrose, cellobiose, inulin and starch) in aqueous media.
|Number of pages||14|
|Journal||New Journal of Chemistry|
|Publication status||Published - 19-Oct-2020|
- fructose, ionic liquids, 5-hydroxymethylfurfural, stabilization effect, aqueous media.