Suppression of oligomer formation in glucose dehydration by CO₂ and tetrahydrofuran

Abstract

The synergetic action of tetrahydrofuran (THF) and low-pressure CO2 (1.0 MPa) is favourable for effective inhibition of humin precursor (i.e., oligomer) formation in the conversion of glucose to 5-hydroxymethylfurfural (HMF).

Acid‐Catalyzed Conversion of Carbohydrates into Value‐Added Small Molecules in Aqueous Media and Ionic Liquids

“…In an unusual setup, glucose can be converted into HMF in a mixture of water/THF under the pressure of carbon dioxide . Notably, under the applied conditions, this medium forms a triphasic system, H 2 O–CO 2 (liquid)/THF–CO 2 (liquid)/CO 2 (gas), which results in high yield and selectivity of HMF (Table ).…”

“…It is apparent that CO 2 possesses Lewis acidity, whereas in situ generated H 2 CO 3 offers Brønsted acidity; therefore, the reaction medium contains the acid catalyst requisite to the transformation of glucose into the major product. Usefully, the process requires only a mild pressure of CO 2 (1 MPa) and enables relatively easy recovery of products and solvents . Application of the process to polysaccharides will prove interesting from a scientific and practical perspective.…”

“…In an unusuals etup, glucose can be convertedi nto HMF in am ixture of water/THF under the pressure of carbon diox- ide. [93] Notably,u nder the applied conditions, this medium forms at riphasic system, H 2 O-CO 2 (liquid)/THF-CO 2 (liquid)/ CO 2 (gas), which resultsi nh igh yield and selectivity of HMF (Table 1). It is apparent that CO 2 possessesLewis acidity,whereas in situ generated H 2 CO 3 offers Brønsted acidity;t herefore, the reactionm edium contains the acid catalyst requisite to the transformationo fg lucose into the major product.…”

“…Usefully,t he process requires only am ild pressure of CO 2 (1 MPa) and enables relatively easy recovery of products and solvents. [93] Application of the process to polysaccharides will prove interesting from as cientifica nd practical perspective. There remains ad rive towards the efficient synthesis of HMF directly from cellulose in as ingle water phase to avoid the use of organic solvents in high-temperature processes.…”

Effect of Heating Rate on Yields and Distribution of Oil Products from the Pyrolysis of Pubescen

“…Parts of oligosaccharide, glucose, fructose, HMF, xylose, xylulose, furfural, lactic acid, formic acid, and acetic acid interacted with each other and then formed oligomers, some of which were identified by ESI‐MS (shown in Tables S2–S4 in the Supporting Information). There were some specific structures of oligomers derived from carbohydrates, which have been reported in our previous study …”