超声场中亚油酸共轭反应的动力学

Kinetics of Conjugation of Linoleic Acid in Ultrasonic Field

在超声作用下,假设亚油酸共轭反应为不可逆恒容反应,且反应一步完成的基础上,研究了碱催化亚油酸共轭反应的动力学。考察了反应物与催化剂的浓度、超声声强、温度对共轭反应速率的影响,并通过理论推导与试验拟合得到了各因素对反应速率常数影响的数学模型。结果表明,在超声作用下,碱催化亚油酸共轭反应符合宏观一级动力学特征;超声声强、反应物初始浓度、温度及催化剂浓度对反应速率的影响较大。在超声作用下反应的表观活化能为112.1 k J/mol,与常规相比,有所降低,这说明,超声作用可以使共轭反应进行得更快。试验同时显示,所得到的模型对试验结果的预测非常好,可用于超声作用下亚油酸共轭反应结果的预测。

Kinetics of alkali - catalyzed conjugation of linoleic acid with assistance of ultrasound has been researched in the paper. Providing that the reaction could be finished in one step and the process was irreversible with a constant -volume, the effects of reactant concentration, catalyst concentration, the ultrasonic intensity and temperature on the reaction rate have been investigated on the foundations. The mathematic model of all factors affecting the reaction constant was also established though theoretical derivation and test fitting. The results showed that the alkali - catalyzed conjugation of linoleic acid assisted by ultrasound was conformed to the kinetic characteristics of macro level. The ultrasonic intensity, initial linoleic acid concentration, catalyst concentration and temperature had very important influence to the reaction rate. The apparent activation energy of conjugation in ultrasonic field, 112 kJ ·mol^-1, was lower than that of the common method. Further, the reaction will be faster than that of the common method. It was also investigated that the predictions from the model could provide a perfect description for the process of the reaction which could be used in reality.