Process for preparing 5-hydroxymethyl-furfural

The invention relates to a preparation method for 5-hydroxymethyl furfural, which belongs to production technology of chemicals, in particular to a method for synthesizing 5-hydroxymethyl furfural (HMF) from carbohydrates by adopting a catalytic way. The method for preparing the 5-hydroxymethyl furfural uses heteropolyacid or heteropolyacid salt as a catalyst, and the 5-hydroxymethyl furfural with high purity can be obtained at a high yield by modulating the catalyst activity, choosing proper solvents, adding additives, optimizing the reaction temperature and time and improving the post treatment technologies, and the corrosion to devices and the environmental pollution can be avoided when using liquid super acids. In the system of saturated sodium chloride solution-positive butanol, the yield of the HMF can reach 70 percent under the catalysis reaction of phosphotungstic acid for 4 minutes at 175 DEG C.