Method of synthesizing 5-hydroxymethyl furfural

Abstract

A method of synthesizing 5-hydroxymethyl (5-HMF) furfural includes a step of adding an alcohol ether substance into an ionic liquid reaction system to achieve high-effective synthesis of the 5-HMF, wherein the alcohol ether substance includes following compounds, which are soluble, partial soluble or non-soluble with the ionic liquid: ethyl glycol dimethyl ether, propylene glycol dimethyl ether, polyethylene glycol dimethyl ether, polyethylene glycol, polypropylene glycol dimethyl ether, propylene glycol and polypropylene glycol, to form a homogeneous phase or double phase system with the ionic liquid. In the reaction system, a small-molecular additive can be selectively added and the 5-HMF is synthesized with a substance containing glucose or fructose as raw materials, wherein the substance may be: cellulose, oligomerization cellulose, semi-cellulose, starch, glucose and fructose. For example, adding the ethyl glycol dimethyl ether to a [BMIM]Cl / CrCl3.6H2O catalytic system with addition of less amount of ethanol additive, a glucose raw material being 80 wt% on the basis of the mass of the ionic liquid is high-effectively converted into 5-HMF, wherein the yield of the reaction is 1.85 times than that of a reaction without the ethyl glycol dimethyl ether and the ethanol additive. The method can be used for high-effectively synthesizing the 5-HMF from a lignocelluloses derivative.

Description

technical field [0001] The invention belongs to the technical field of chemical reaction, and in particular relates to a method for synthesizing 5-hydroxymethylfurfural. Background technique [0002] 5-Hydroxymethylfurfural (5-hydroxymethylfurfural, 5-HMF or HMF) is produced by dehydration of glucose or fructose. The molecule contains a furan ring, an aldehyde group and a hydroxymethyl group. Its chemical properties are relatively active and can be oxidized, It is an important fine chemical raw material for the preparation of various derivatives through reactions such as hydrogenation and condensation. On the other hand, the direct raw materials for the synthesis of 5-HMF—glucose and fructose—can be obtained from biomass. The non-renewability of fossil resources and the huge consumption of them by humans make them gradually exhausted. The development and utilization of green and environmentally friendly renewable resources is an inevitable choice for the healthy development...

AI Technical Summary

Problems solved by technology

The problem faced by the conversion reaction of carbohydrates in ionic liquids is: the viscosity of ionic liquids is relatively high, and when high-concentration raw materials are used, the reaction effect is not ideal, for example, when 10-20wt% (relative to the mass of ionic liquids) Glucose raw material, the yield of 5-HMF can reach 60-70%, but when using 50-100wt% (relative to the mass of ionic liquid) glucose raw material, the yield of 5-HMF is only 20-30%

Therefore, how to realize the high-efficiency conversion of high-concentration glucose in ionic liquids to synthesize 5-HMF is an important technical link to promote its industrial production, but there has been no research report on effectively solving this problem so far.

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