离子液体催化合成亚油酸植物甾醇酯

摘要

研究了离子液体在亚油酸植物甾醇酯合成中的应用.从[ Bmim] BF4、[Bmim] CF3SO3ChCl·2SnCl2、ChCl·2ZnCl2、ChCl·2.5SnCl2和ChCl·2FeCl3中筛选ChCl·2SnCl2为实验的催化剂,并用吡啶探针法测定了各种离子液体的酸性.通过对酯化率和反应氧化程度的考察,确定最佳反应条件为:离子液体用量为植物甾醇质量的8％,酸醇摩尔比2∶1,反应温度160℃,反应时间4h,经3次平行实验测得平均酯化率为89.73％.合成反应后,离子液体与酯化产物成两相,而且离子液体ChCl·2SnCl2在重复使用5次后仍有较高催化活性.%Phytosteryl linoleate synthesized from natural phytosterol and linoleic acid in the presence of ionic liquids as catalysts was investigated. [ Bmim ] BF4 , [ Bmim ] CF3 S03, ChCl ? 2SnCl2, ChCl ? 2ZnCl2, ChCl ? 2. 5SnCl2 and ChCl ? 2FeCl3 were evaluated to determine the best catalyst, and the Lewis acidity of the ionic liquids was determined by pyridine as IR spectroscopic probe. The results showed that ChCl ? 2SnCl2 was more suitable in this study, and the average yield of phytosteryl ester reached 89. 73% when the esterification reaction was carried out at 160 X, for 4 h with linoleic acid and phytosterol in a molar ratio of 2:1 and 8% ionic liquid. The catalyst recovery experiments suggested that ChCl ? 2SnCl2 did not significantly lose its activity in five operation runs.