均相酸催化纤维素水热转化制备乙酰丙酸研究

Research on the hydrothermal conversion of cellulose to levulinic acid catalyzed by homogeneous acid

乙酰丙酸的分子结构具有羧基、羰基等官能团,具有高反应活性,可转化为生物液体燃料及各种高值化学品,是一种重要的平台化合物。使用稀硫酸和马来酸等均相催化剂,在水相中催化微晶纤维素水热转化制备乙酰丙酸,研究反应参数对糖分子及其衍生物总产率、乙酰丙酸得率的影响。结果发现,在常压、180℃、90 min、5%硫酸浓度条件下,糖分子及其衍生物总产率达81.23%。当反应温度升高至190℃时,糖分子及其衍生物总产率降低,乙酰丙酸得率、选择性分别为73.64%、92.12%。研究结果可为纤维素水热转化制备乙酰丙酸提供参考。

The molecular structure of levulinic acid has functional groups such as carboxyl and carbonyl groups,which h is an important platform compound with high reactivity and can be converted into bio-liquid fuels and various high-value chemicals.In this paper,levulinic acid was prepared by hydrothermal conversion of microcrystalline cellulose in the aqueous phase catalyzed by homogeneous catalysts including dilute sulfuric acid and maleic acid.The effects of reaction parameters on the yields of sugar molecules and their derivatives,especially levulinic acid,were studied.The results showed that the total yield of sugar molecules and their derivatives was up to 81.23% at 180℃,90 min,and 5.% acid concentration at atmospheric pressure.When the temperature was increased to 190℃,the total yield of sugar molecules and their derivatives began to decrease,and the yield of levulinic acid reached 73.64%,while its product selectivity was 92.12%.The results of the present work provide useful references for hydrothermal conversion of cellulose to efficiently produce levulinic acid.