中文摘要：

为了研究溶剂效应对单糖转化制取5-羟甲基糠醛（HMF）的影响，考察了葡萄糖在3种不同溶剂（水、二甲亚砜（DMSO）、水-DMSO）下较宽温度范围内（100～200℃）无催化条件下的降解行为，实验结果显示，在175℃水．DMSO混合溶剂下，HMF的产率可达到20．7％，远高于水溶剂下的11．86％和DMSO溶剂下的10．0％。采用涉及5-羟甲基糠醛（HMF）、乙酰丙酸（LA）和腐殖质（humin）生成的反应模型分析了葡萄糖降解动力学，该模型较好地吻合了实验结果。动力学分析表明，DMSO的存在改变了葡萄糖的异构化途径并生成了果糖和半乳糖，同时抑制了HMF进一步发生再水合反应生成LA和发生聚合反应生成humin。此外，针对humin的结构表征进一步揭示了水和DMSO对humin生成的不同作用机制。

英文摘要：

As a high value-added platform chemical in biorefinery, 5-hydroxymethylfurfural （HMF） can undergo conversion to various fine chemicals and high quality liquid fuels. Glucose decomposition in liquid-phase system is the conventional route for HMF production. To get insights into the effects of different solvents on HMF formation, the conversion of glucose in three different solvents, including water, dimethylsulfoxide （DMSO） , and water-DMSO mixture, was performed over the temperature range of 100℃ to 200℃. The results showed that the yield of HMF in water-DMSO mixture at 175℃ was up to 20.7% , which was much higher than that in pure water （11.86%） and DMSO （10.0%）. A reaction model involving the formation pathways of HMF, levulinic acid （LA） and humin was used to analyze the kinetics of glucose decomposition, and the obtained kinetic parameters predicted experimental results very well. It was found that DMSO altered the path of glucose isomerization, resulting in the formation of fructose and galactose. Compared with the enhancement of HMF activity in water, DMSO suppressed the further reaction of HMF to form LA and humin. Moreover, the properties of the humins generated in the three solvents were characterized, and the corresponding formation mechanisms were discussed.