【摘要】 采用自制的GDCH-2012圆柱状颗粒催化剂,对苯胺加氢联合制备环己胺和二环己胺反应的宏观动力学进行研究。在固定床反应器中,催化剂分3个单层,层间用石英砂均匀间隔。在高温、低苯胺流量、低苯胺与H2摩尔比的条件下消除了外扩散的影响。在温度180~240℃、压力0.3 MPa、苯胺进料流量0.013 2~0.158 mol/h、苯胺与H2摩尔比(氢胺比)(10~20)∶1条件下测定宏观动力学的实验数据,并建立宏观反应动力学模型。以苯胺的转化率、二环己胺的收率以及N-环己基苯胺收率的残差平方和为目标函数,采用Matlab软件中的非线性最小二乘法对实验数据进行拟合,估算出该模型中的各个参数,并对模型的显著性进行了检验。结果表明:模型计算值与实验测定值吻合良好,且模型是高度适定的。通过计算还得到了氢胺比(10~20)∶1、反应温度180~240℃、不同苯胺转化率下的催化剂内扩散有效因子。更多还原

【Abstract】 The macrokinetics of aniline hydrogenation was investigated on self-made GDCH-2012 nonnoble metal catalyst for improving the selectivity of dicyclohexylamine for aniline hydrogenation. The catalysts were packed in a fixed bed reactor with three layers and were saparated by quartz sand evenly to ensure that the reactant gases flow through the catalyst bed without backmixing. The external diffusion influence was eliminated under condition of high temperature,low aniline flow,and low molar of H2 to aniline. The experiments were carried out under the following conditions:the temperature of 180-240 ℃,the pressure of 0. 3 MPa,the molar ratio of hydrogen to aniline of(10-20) ∶ 1,and the aniline flow of0. 013 2-0. 158 mol/h. The kinetics model was established after the reaction network of aniline hydrogenation was determined with the analysis of the product composition and the reaction mechanism.The minimum residual sum of squares between the calculated values and the experimental ones of anilineconversion,dicyclohexylamine yield and N-cyclohexylaniline yield were used as the objective function.The parameters were obtained by nonlinear least-square method of Matlab software and the significance testing of the model was carried out. Results showed that the macrokinetics model for hydrogenation of aniline was reasonable and could describe hydrogenation of aniline. The intraparticle diffusion efficiency factor with conversion of aniline was calculated when the molar ratio of hydrogen to aniline was(10-20)∶ 1 and temperature was 180-240 ℃.更多还原