5-羟甲基糠醛(HMF)是一种链接可再生生物质资源与燃料化合物及化学中间体的重要新型平台化合物。文中对高温(180-200℃)条件下,金属氯化物为催化剂,离子液体[BMIM]Cl为溶剂,木质纤维素(相思木木屑)为原料快速制备HMF和糠醛的反应过程进行了研究。通过对反应温度、原料用量、盐酸(HCl)添加量、催化剂种类及用量等因素进行考察,优化了反应条件。研究结果表明:与文献报道的低温下纤维素降解反应相比,高温条件可使木质纤维素为原料制备HMF的反应过程得到强化。在所考察的金属氯化物催化剂中,CrCl3·6H20的催化效果最优,其中以CrCl2·6H20为催化剂,200℃下反应4min时产物HMF及糠醛的收率分别可达55.0%和22.9%。该高温反应过程反应快速、产物收率高,无需木质纤维素原料的预处理操作,为工业上简单快速制备HMF提供了一种可行方法。
5-hydroxymethylfurfural (HMF) is a potentially important platform chemical that connects renewable biomass feedstock with the future industrial production of biofuels and chemical intermediates. A reaction process toward rapid production of HMF and furfural from acacia wood chips was investigated at 180-200 ~C, using metal chloride catalysts in 1-butyl-3-methylimidazolium chloride ( [ BMIM ] C1) solvent, with lignocellulosic biomass as feedstock. Several key factors including reaction temperature, concentration of raw wood chip materials in the solvent, hydrochloric acid (HC1) concentration, catalyst species and loading, etc. were studied in order to optimize the reaction condition. The results show that the production of HMF from lignocellulosic biomass is greatly accelerated under a higher temperature compared with that reported in the literature for cellulose conversion. Among the chosen metal chlorides, CrC13 ~ 6H20 shows the best catalytic performance. Under the optimized reaction conditions, with CrC13 ~ 6H20 as catalyst, HMF and furfural yields can reach 55.0% and 22.9% respectively at 200 ℃ in 4 min. This high-temperature reaction process is rapid and cost-effective for the industrial production of HMF and furfural, and there is no need for pretreatment of lignocellulose biomass before reaction.