油脂中不同位置脂肪酸氢化速率的研究

STUDY ON HYDROGENATION RATE OF FATTY ACIDS IN THE INDIVIDUAL POSITION OF TRIGLYCERIDES

通过大豆油和玉米油在相同的氢化反应条件下 ,用不同的催化剂选择性氢化 .运用反应比、lnIv t图及速率常数计算等不同方法 ,论证脂肪酸在甘三酯不同位置上的氢化速率是否相同 .结果表明 :大豆油氢化时 ,亚麻酸、亚油酸、油酸在Sn - 1 ,3位较Sn - 2位氢化反应得更快 ;玉米油氢化时 ,亚油酸在Sn - 1 ,3位氢化速率大于Sn - 2 ,而油酸在甘三酯不同位置上的氢化速率差异因催化剂不同而有所区别 ,对大多数催化剂来说 ,Sn - 1 ,3位氢化速率大于Sn - 2位 ,用催化剂SP7催化氢化时 。

In this paper,partial hydrogenation of soybean and corn oil were carried out with different catalysts under the same conditions of experiments.Hydrogenation rate of fatty acids in different positions of triglycerides was discussed by the reaction ratio of fatty acids,reaction rate constants and lnIv-t figure.It showed that the hydrogenation of fatty acids in soybean oil took place at different rates in the individual positions of triglycerides,it is faster in position 1,3, than in position 2.From the hydrogenation of corn oil we found that C18∶2 acid had greater reaction rate in positions 1,3 than that of position 2.In regard to C18∶1 acid,however,the diversity of the hydrogenation rate in the individual positions was varied with different catalysts.The results,for most of catalysts,suggest that it is faster in position 1,3 than in position2,while the difference disappears with catalysts SP7.