异佛尔酮腈亚胺化反应动力学研究

A Kinetic Study of Imination of Isophorone Nitrile

异佛尔酮腈（IPN）与氨反应生成异佛尔酮腈亚胺和水，此反应是可逆反应，其逆反应为席夫碱的水解反应。为了获得IPN的亚胺化反应动力学方程，以IPN和氨气为原料、甲醇为溶剂，考察了303.15～333.15 K下氨腈摩尔比b=5、13、21的亚胺化反应。采用气相色谱分析，测定了IPN的浓度随时间的变化，数据拟合获得了氨腈比＞1、产物初始浓度为零、恒容条件下亚胺化的反应速率方程。结果表明，反应焓变DH为-17.417 kJ·mol-1；正反应的表观活化能Ea为23.043 kJ·mol-1，指前因子ka0为8.804·103 L·（mol·s）-1；逆反应的表观活化能Eb为40.461 kJ·mol-1，指前因子kb0为5.638·106 L·（mol·s）-1。对获得的动力学方程进行了验证，转化率的实验值与计算值符合较好。获得的动力学方程为深入研究IPN的亚胺化提供了重要的参考，为工业化提供了相应的指导。

Isophorone nitrile（IPN） reacts with ammonia to form isophorone imine and water, the reaction is reversible, and its reverse reaction is the hydrolysis of Schiff base. In order to obtain the imination kinetic equation of IPN, imination reactions were investigated with using methanol as the solvent under 303.15～333.15 K, with ammonia/IPN mole ratiosβ=5,β=13 andβ=21, respectively. Gas chromatography was employed to measure the concentration of IPN with time, and the imination rate equation was obtained by fitting experimental data;however the obtained equation is for the ammonia/IPN ratio＆gt;1, the initial concentration of products is zero and for the condition of constant volume. The results show that the enthalpy of the reactionΔH is-17.417 kJ·mol-1;the apparent activation energy of the forward reaction Ea is 23.043 kJ·mol-1, the reaction pre-exponential factor ka0 is 8.804·103 L·（mol·s）-1;the apparent activation energy of the backward reaction Eb is 40.461 kJ·mol-1, the reaction pre-exponential factor kb0 is 5.638·106 L·（mol·s）-1. The obtained kinetic equation was verified, and the conversion calculated from the obtained equation is in good agreement with the experimental data. The kinetic equation provides important information for a deeper study of imination of IPN and gives responding guidance on its industrialization.