[emim]BF_4离子液体催化酯化反应研究

Esterification catalyzed by BF_4 ionic liquid

研究了环境友好的[emim]BF4离子液体催化亚油酸等高碳脂肪酸与无水乙醇酯化反应,考察了亚油酸与乙醇的摩尔比、反应温度、离子液体用量等条件对亚油酸酯化反应结果的影响,优化了反应的工艺条件。适宜的反应条件为:n(乙醇)∶n(亚油酸)=4∶1,回流反应温度,[emim]BF4用量为反应物质量的42%。结果表明[emim]BF4离子液体对亚油酸等脂肪酸的酯化反应显示了优异的催化活性,亚油酸酯化率最高可达94%。反应产物与离子液体易于分离,离子液体循环使用5次以上,酯化率没有明显降低。

The esterification of linoleic acid and high-carbon fatty acid with anhydrous ethanol in ionic liquid [ emim] BF4 as an environment-friendly catalyst have been investigated. The effects of molar ratio of linoleic acid and ethanol, temperature, and amount of ionic liquid on esterification reaction were studied and the optimal reaction conditions were obtained, that is, n （ethanol） ： n （linoleic acid） = 4 ： 1, at refluence temperature, with the amount of ionic liquid equaling 42 （ wt. ） % of reacting matters. The results showed that [emim]BF4 has good activity for esterification of linoleic acid with ethanol, the conversion of linoleic acid reached 94 %. The ionic liquid could be conveniently separated from the products and reused directly without any treatment for over 5 times, and the conversion rate didn＇t go down obviously.