脂肪酸甲酯环氧化反应机理及动力学研究

Mechanism and Kinetic Research of Fatty Acid Methyl Ester Epoxidation

以脂肪酸甲酯为原料,对甲酸/过氧酸法制备环氧脂肪酸甲酯过程中的环氧化反应动力学进行了研究,建立了表观总包反应动力学模型,并揭示了脂肪酸甲酯环氧化反应机理。结果表明,此环氧化反应由双键环氧化、酸性条件环氧键开环以及环氧键水解三个基元反应耦合而成。通过对比各基元反应的动力学参数发现,双键环氧化和环氧键开环反应同步发生,双键环氧化反应速率为总包反应控速步骤,环氧键水解并未产生明显开环作用。此外,对最优工况进行了探究,可为工艺优化设计提供一定的指导意义。

In this paper, fatty acid methyl esters are used as raw materials to study the epoxidation reaction kinetics during the preparation of epoxy fatty acid methyl esters by the formic acid/peroxy acid method. The apparent total package reaction kinetic model was established, and the mechanism of fatty acid methyl ester epoxidation reaction was revealed. The results show that the epoxidation reaction is composed of three elementary reactions, namely, double bond epoxidation, epoxy bond ring opening under acidic conditions, and epoxy bond hydrolysis. By comparing the kinetic parameters of each elementary reaction, it is found that the double bond epoxidation and the epoxy bond ring-opening reaction occur simultaneously. The double bond epoxidation reaction rate is the rate-controlling step of the total package reaction, and the epoxy bond hydrolysis does not produce significant open-loop effect. In addition, the optimal working conditions are explored, which can provide certain guiding significance for process optimization design.