植物甾醇酯的绿色合成技术研究

Synthesis of Phytosterol Esters Using Solid Green Catalyst

研究了植物甾醇与脂肪酸直接酯化合成植物甾醇酯的绿色化学合成工艺。试验筛选得到了安全、绿色、高效的催化剂ZnO。脂肪酸选择性试验表明ZnO对大多脂肪酸没有明显的选择性,但优先作用亚油酸,而对硬脂酸活性不高。较优的工艺条件为:ZnO用量为0.5%,油酸与甾醇的摩尔比为2∶1,反应温度170℃,氮气保护,反应时间8 h,此条件下反应酯化率为95.2%,反式脂肪酸的生成也得到了明显的抑制。

A green chemical synthesis technology of phytosterol esters from phytosterols and free fatty acids was investigated in this work. ZnO, which is characteristic of safe, environmental friendly and high efficiency, was the preferred catalyst for the phytosterol esters synthesis. A trial showed that ZnO has no significant selectivity for most fatty acids, preference for linoleic acid and rather low esterification activity for stearic acid. The proper reaction conditions are molar ratio of oleic acid to phytosterol 2： 1, ZnO dose 0.5 %, reaction at 170℃ under a nitrogen flow for 8h. Under the conditions a sterol ester yield of 95.2 % can be reached, and the formation of trans - fatty acids is inhibited significantly.