Phase Modifiers Promote Efficient Production of Hydroxymethylfurfural from Fructose

Abstract

Furan derivatives obtained from renewable biomass resources have the potential to serve as substitutes for the petroleum-based building blocks that are currently used in the production of plastics and fine chemicals. We developed a process for the selective dehydration of fructose to 5-hydroxymethylfurfural (HMF) that operates at high fructose concentrations (10 to 50 weight %), achieves high yields (80% HMF selectivity at 90% fructose conversion), and delivers HMF in a separation-friendly solvent. In a two-phase reactor system, fructose is dehydrated in the aqueous phase with the use of an acid catalyst (hydrochloric acid or an acidic ion-exchange resin) with dimethylsulfoxide and/or poly(1-vinyl-2-pyrrolidinone) added to suppress undesired side reactions. The HMF product is continuously extracted into an organic phase (methylisobutylketone) modified with 2-butanol to enhance partitioning from the reactive aqueous solution.

Liquid‐Phase Catalytic Processing of Biomass‐Derived Oxygenated Hydrocarbons to Fuels and Chemicals

“…Use of all three modifiers (DMSO, PVP, and 2-butanol) at 30 wt % fructose concentration afforded 83 % selectivity for HMF at 82 % conversion. [67] Increasing the concentration from 30 to 50 wt % decreased the HMF selectivity owing to higher rates of condensation reactions, but doubling the amount of the extracting solvent (7:3 MIBK/2-butanol mixture) increased the selectivity substantially. Experiments conducted at low fructose conversions in pure water and in the presence of 20 wt % DMSO indicated that DMSO enhances the rate of fructose conversion and decreases the rates of undesired parallel reactions.…”

“…[67] In a two-phase reactor system, the fructose is dehydrated in the reactive aqueous phase in the presence of HCl as acid catalyst with DMSO and/or poly(1-vinyl-2-pyrrolidinone) (PVP) added as modifiers to suppress the formation of by-products. The HMF product is continuously extracted into an organic phase (methylisobutylketone, MIBK) modified with 2-butanol to enhance partitioning from the reactive aqueous solution.…”

“…In this respect, results using acidic ion-exchange catalysts at low temperature (363 K) showed lower selectivity for HMF in the presence of modifiers; however, promising results (e.g., 73 % HMF selectivity) were obtained using niobium phosphate at higher temperatures (453 K). [67] It is anticipated that these results can be further improved by synthesizing new catalytic materials such as nanoporous MCM-based materials which contain sulfonic acid groups that promote dehydration of xylose to furfural at elevated temperatures. [71] Also, while various polysaccharides can be processed with the biphasic reactor approach using higher levels of DMSO, separation of HMF from DMSO in the organic phase still remains an issue.…”

Phosphotungstic Acid Encapsulated in Metal–Organic Framework as Catalysts for Carbohydrate Dehydration to 5‐Hydroxymethylfurfural

“…For instance, fructose can be dehydrated to HMF in dilute HCl, but side reactions result in the formation of highly condensed products, which are usually called humins. [5] Dehydration of glucose to HMF is much more challenging. Unprecedented yields of HMF have been reported for chromium halides and N-heterocyclic carbene-chloride complexes in ionic liquid media.…”

Dehydration of Glucose to 5‐Hydroxymethylfurfural Using Nb‐doped Tungstite

“…Lewis acids are preferred because their activity is not affected by strong Brønsted acids 4. Selective dehydration of fructose to HMF can be readily achieved in the presence of Brønsted acid catalysts in biphasic organic–water solvents 5, 6, 7…”