离子液体-金属盐催化玉米粉制乙酰丙酸甲酯的研究

Preparation of methyl levulinate from corn starch with metal salt/1,3-dialkyl imidazolium as catalyst

在甲醇介质中,以生物质原料玉米粉为底物,进行了离子液体1,3-二甲基咪唑硫酸氢盐([DMIM]HSO4)和金属盐共同催化玉米粉制备乙酰丙酸甲酯的研究。研究发现一系列铝盐对转化玉米粉生成乙酰丙酸甲酯有较好的催化性能,尤其是在铝盐中加入离子液体1,3-二甲基咪唑硫酸氢盐([DMIM]HSO4)时,可明显提高乙酰丙酸甲酯的收率。优选其中的一种铝盐,研究了反应时间、反应温度、催化剂用量对乙酰丙酸甲酯收率的影响。在反应温度140℃、反应时间3 h和0.700 g离子液体协同0.300 g硫酸铝的共同催化下,乙酰丙酸甲酯的摩尔收率高达51%。

Several aluminum salts show the better catalytic activity on conversion of corn starch to methyl levulinate than the other metal salts in methanol at mild conditions, especially A12 （SOa）3 ·18H2O. In this process, ionic liquid 1,3- dimethylimidazolium hydrogen sulfate（ [ DMIM ] HSO4） as a co-catalyst can enhance the yield of methyl levulinate. The effects of reaction time, reaction temperature, and catalyst loading on methyl levulinate yield are studied. The optimal reaction conditions are shown as follows ： 140℃ of reaction temperature, 3 hours of reaction time, 0. 700 g of [ DMIM ] HSO4 and 0. 300 g Al/（ SO4 ）3·18H2O as catalyst. The molar yield of methyl levulinate can reach 51%.