己二腈催化加氢的动力学研究

Study on the Dynamics of Catalytic Hydrogenation of Adiponitrile

对间歇高压釜中进行的雷尼镍催化己二腈加氢的反应动力学进行了研究.通过考察反应过程己二腈、氨基己腈以及己二胺的浓度随时间变化的规律,可计算得到各步反应的反应级数、指前因子和活化能等动力学参数.结果表明,在消除内、外扩散影响的情况下,328～358 K的温度范围,2～3.5 MPa的压力范围内,己二腈加氢成为氨基己腈的过程对己二腈呈一级反应,对氢气呈1.4级反应;氨基己腈继续加氢制备己二胺的过程对氨基己腈为零级反应,对氢气为1.3级反应.在此基础上建立了己二腈催化加氢制备己二胺的各步反应的动力学方程,并对动力学方程进行了验证.

The kinetics for hydrogenation of adiponitrile were studied with Raney nickel as catalyst in a a high-pressure batch reactor.Under the condition of no inside and outside diffusion,the concentration of adiponitrile,aminocaproic nitrile and hexamethylenediamine versus time over the Raney-Ni catalyst were measured.The kinetic parameters of catalytic hydrogenation of adiponitrile to hexamethylenediamine such as reaction order,pre-exponential factor and activated energy in each step were obtained.The results show that,when the temperature kept at 328~358K and pressure kept at 2~3.5MPa,the order of adiponitrile hydrogenation to adiponitrile was 1,while to hydrogen pressure was 1.4.The intermediate aminocaproic nitrile was hydrogenated to hexamethylene diamine,the reaction order to aminocaproic nitrile was 0,to hydrogen pressure was 1.3.Based on these results,the kinetic equations of adiponitrile hydrogenation to hexamethylenediamine in each step were proposed.They are in consistence with the experimental data.