植物油脂的热分析及动力学研究

Study on thermal analysis and kinetic of edible oil

研究了豆油、菜籽油、花生油三种食用油脂的热氧化特性及它们的活化能,详细考察了升温速率、气氛以及气体流速对它们热氧化行为的影响。当升温速率分别采用5、10、20K/min时,对于同种油,随着升温速率增加,它们的氧化峰向高温方向移动,而且峰形变化大而尖锐;当气氛为氮气时,DSC曲线无热流峰。TG曲线表明,菜籽油的稳定性最高,花生油次之,豆油的稳定性最低。利用常用的微分算法Kissinger和积分算法Ozawa分别计算了三种油脂氧化反应时的活化能,实验结果与文献吻合很好。

Thermal oxidation and activation characteristics of three types edible oils were performed, which were soybean oil, rapeseed oil, peanut oil.Experimental parameters including the heating rate, the atmosphere and the gas flow rate of thermal oxidation were detailed considered.With the increasing of heating rate, the oxidation peak moved to the high temperature and peak shape became large and sharp,when the heating rates were used 5,10, 20K/rain for the same oil.When the atmosphere was nitrogen, DSC-TG curves showed that the highest stability of rapeseed oil,peanut oil followed the stability of soybean oil minimum.Differential algorithm Kissinger and Integral algorithm Ozawa were used to calculate the oxidation activation energy.The experimental results were in good agreement with the literature.