[Bmim]Cl中CrCl_3-AlCl_3催化纤维素降解制取5-羟甲基糠醛

Conversion of cellulose into 5-hydroxymehylfurfural catalyzed by CrCl_3-AlCl_3

5-羟甲基糠醛是一种具有很高利用价值的化学平台化合物。以离子液体1-丁基-3-甲基咪唑氯盐([Bmim]Cl)为溶剂,以CrCl_3和AlCl_3为复合催化剂,在油浴加热条件下催化纤维素降解制取5-羟甲基糠醛,研究了催化剂种类、催化剂量、温度、纤维素浓度、气氛、纤维素聚合度、反应规模等不同因素对纤维素降解制取5-羟甲基糠醛的影响。结果表明,[Bmim]Cl用量为10 g,棉花添加量为0.5 g,x(CrCl_3)=25%(mol),x(AlCl_3)=2.5%(mol),反应温度为120℃,反应气氛为N2(dry)气氛,反应时间为4 h时,HMF产率最高,达到59%。此外,反应过程中水的作用机理也被给予了相应解释。

5-Hydroxymehylfurfural（HMF）, as a valuable platform chemical compound, can be obtained by the direct catalytic conversion of cellulose. The composite catalyst of CrCl3 and AlCl3 was used to convert cellulose into HMF in 1-butyl-3-methyl imidazole chloride（[Bmim]Cl） under oil-bath heating. The effect of catalyst dosage, temperature, cellulose amount, atmosphere, polymerization degree and reaction scale were investigated. The highest HMF yield of 59% was obtained at 4 h when 0.5 g cotton was added into [Bmim]Cl with 25%—2.5% dosage of CrCl3-AlCl3 at 120℃ under N2（dry） atmosphere. The production efficiency was improved while the cost was reduced. Additionally, the mechanism of degradation of cellulose was proposed.