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5 - hydroxymethylfurfural (5-HMF) is an important bio-chemical raw materials, transformation of monosaccharides Preparation of 5 - (hydroxymethyl) furfural reaction is an important part of the biomass utilization, usually a liquid acid catalyst, there is severe corrosion of the equipment, it is difficult to recycling and other issues. The papers prepared by ionic liquids heteropoly salt, low corrosive, environmentally friendly catalysts and catalytic monosaccharides (glucose and fructose) conversion of these catalysts Preparation of 5 - hydroxymethylfurfural (5-HMF) reaction , also investigated the various reaction conditions such as solvent, reaction time, reaction temperature, heating method, etc. on the reaction. In this thesis, prepared three imidazolium ionic liquid catalyst: [BMIM] Cl, [BMIM] Br and [EMIM] Br; impregnation method of synthesis six phosphotungstate: CePW12O40 Cs2.5PW12O40, Ni1.5PW12O40, Cu1 .5 PW12O40, Zn1.5PW12O40, BiPW12O40, the prepared catalysts were characterized by infrared spectroscopy and XRD, and found that the synthesis of ionic liquids has the characteristic structure of the imidazole-based ionic liquids, phosphotungstic acid with Keggin structure and not because of the metal ion. introduction changed. Secondly, the solid acid as the catalyst, the conversion of 5 - (hydroxymethyl) furfural reaction conditions were studied to fructose. The results show that: (1) the solid acid, the catalytic activity of the phosphorus tungstate highest; six phosphotungstate Catalyst fructose reaction in the reaction of 5 - (hydroxymethyl) furfural, larger metal ions Cs Ce3 are formed on the catalyst than the larger surface area, strong acid, preferably a catalytic effect of Cs2.5PW12O40; (2) phosphotungstic acid cesium salt as a catalyst, the reaction temperature is increased and the extended reaction times can increase the 5-HMF yield, suitable substrate concentration and amount of catalyst enables the reaction to obtain a high yield of 5-HMF, both excessive concentrations, the side reactions increase selectively reduced; (3) under optimal conditions (140 ° C, 180 minutes, 10% (wt%) concentration of reactants, 10% (wt%) catalyst concentration), 5 - (hydroxymethyl) furfural yield of up to 98.44%; (4) compared with oil bath heating, microwave heating of the \heating \1) a solid acid catalyst and the ionic liquid catalyst, the catalytic effect of the ionic liquid on the reaction more prominent; three ionic liquids, due to the acidity of the same cationic imidazole-based ionic liquids as determined by the anion and three ionic liquid catalyst activity order: [BMIM] Cl gt; [BMIM] Br gt; [EMIM] Br; (2) to the ionic liquid [BMIM] Cl catalyst to add metal chloride is conducive to the improvement of 5-HMF yield in acidic medium of CuCl2 best results; to add inorganic acid additives can increase the acidity of the reaction system, so that the increase in the yield of 5-HMF, strong oxidizing acids are not suitable for use as an additive to; (3) an organic solvent is added to suppress side reactions occur while promoting the reaction to the positive, wherein the most obvious effect of the DMSO; (4) the reaction temperature is too high or too low are ideal experimental results can not be obtained, have some help prolong the reaction time for product formation, a suitable concentration of reactants conducive reaction; (5) in [BMIM] Cl as catalyst, sec-butanol as the solvent, while adding the methyl isobutyl ketone and dimethyl sulfoxide, hydrochloric acid as the inorganic acid additives, oil-water ratio R is 6.4, and the reaction temperature of 140 ° C, the reaction time of 2 hours, 5 - the hydroxymethylfurfural the yield up to 32.54%.
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