Efficient microwave-assisted synthesis of 5-hydroxymethylfurfural from concentrated aqueous fructose.
Studies on the HCl-catalysed microwave-assisted dehydration of highly concentrated aqueous fructose (27 wt%) to 5-hydroxymethylfurfural (HMF) revealed a significant increase in the fructose conversion rate over the conventional heated systems. Water, being the most benign solvent and therefore ideal for green and sustainable chemistry, normally is a poor solvent for the dehydration process resulting in low HMF selectivities and yields. However, reaction at 200 degrees C with microwave irradiation with a short reaction time of only 1s resulted in good HMF selectivity of 63% and fructose conversion of 52%, while prolonged irradiation for 60s (or more) resulted in nearly full fructose conversion (95%) but lower HMF yield (53%). Decreasing the fructose concentration significantly improved the HMF selectivity, but possibly made the production route less attractive from an industrial point of view due to the resultant low throughput.
Hansen
Thomas S
TS
Department of Chemistry, Technical University of Denmark, Centre for Catalysis and Sustainable Chemistry, DK-2800 Kgs Lyngby, Denmark.
Woodley
John M
JM
Riisager
Anders
A
D003890:Desiccation; D005632:Fructose / Q000737:chemistry*; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D055772:Green Chemistry Technology; D008872:Microwaves; D013696:Temperature; D014867:Water
D014867:Water; D005632:Fructose; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde