2-氯乙醇促进果糖非催化脱水制备5-羟甲基糠醛

2-Chloroethanol-promoted Non-catalytic Dehydration of Fructose into 5-Hydroxymethylfurfural

研究了2-氯乙醇对果糖在离子液体1-丁基-3-甲基咪唑氯盐([C4mim]Cl)中非催化脱水制备5-羟甲基糠醛(HMF)的促进性能。结果表明,2-氯乙醇用量增加、反应温度升高以及反应时间延长均有利于HMF的生成。在适当的反应条件下,果糖可以实现完全转化,HMF的选择性达到95%以上。动力学分析表明,2-氯乙醇的存在可以有效降低果糖脱水转化的活化能,在5 mmol 2-氯乙醇的作用下,活化能为48.3 kJ·mol-1,是果糖在温和条件下形成HMF的关键。此外,根据研究结果,对2-氯乙醇促进果糖在[C4mim]Cl中的非催化脱水转化机理进行初步探讨。

The 2-chloroethanol-promoted non-catalytic dehydration of fructose into 5-hydroxymethylfurfural(HMF)in 1-butyl-3-methylimidazolium chloride([C4mim]Cl)is studied.The dosage of 2-chloroethanol,reaction temperature and time play a key role in the dehydration of fructose,and under the suitable reaction conditions,the full conversion of fructose can be achieved with more than 95%of HMF selectivity.The low activation energy of 48.3 kJ·mol-1 in the presence of 5 mmol of 2-chloroethanol is crucial for dehydration of fructose into HMF at the mild conditions from the kinetics analysis.The mechanism of 2-chloroethanol-promoted frutose dehydration is also proposed primarily.