连续反应精馏法合成席夫碱及其动力学研究?

Synthesis of Schiff base by continuous reactive distillation and its reaction kinetics

针对间歇法合成席夫碱转化率低、放大效应明显、能耗高等问题,为实现工艺放大并优化工业生产过程,提出测定动力学参数并采用连续反应精馏法进行合成。以2-甲基-6-乙基苯胺和甲氧基丙酮为原料,采用间歇法在不同温度下合成了N-(2-甲基-6-乙基苯基)-1-甲氧基丙基-2-亚胺;同时,对连续反应精馏合成过程中反应的回流比、进料位置、进料速度和反应时间等因素进行了讨论。结果表明该反应为拟二级动力学过程,首次获得了不同温度下的反应速率常数、计算出活化能E_a=17.63 kJ×mol^(-1),指前因子A=0.801 0 L×(mol×min)^(-1),还确定了连续反应精馏法的最佳反应条件。此外,该方法也适用于其他多种席夫碱的合成,所制备的目标产物收率均较间歇法高。

Schiff base synthesis by batch methods has problems such as low conversion, scale-up issues and high energy consumption. In order to achieve process scale-up and optimize industrial production, continuous reactive distillation was studied and related kinetic parameters were determined. N-(2-methyl-6-ethylphenyl)- 1-methoxypropene-2-imine was synthesized by batch processes at different temperatures using 2-methyl-6-ethylaniline and methoxyacetone as the raw material. Imine was synthesized by continuous reactive distillation, and reflux ratio, feed position, feed rate and reaction time were discussed. The results show that the reaction is a pseudo-second-kinetic process. Reaction rate constants at different temperatures were obtained. The activation energy Ea = 17.63 kJ·mol^-1 and the pre-exponential factor A = 0.801 0 L·(mol·min)^-1 were calculated. The optimal reaction condition of the continuous reactive distillation method was determined. Moreover, the continuous reactive distillation was applied in the synthesis of other Schiff bases, and the yields were higher than batch methods.