脱乙基型催化剂上二甲苯异构化反应动力学研究

采用微型固定床反应装置研究在SKI-210脱乙基型C₈芳烃异构化催化剂(简称SKI-210催化剂)上二甲苯异构化反应动力学。反应网络包括3种二甲苯异构体之间的异构化主反应以及二甲苯的歧化副反应，以Langmuir-Hinshelwood-Hougen-Watson(LHHW)方程模拟反应速率，使用gPROMS软件拟合得到反应动力学参数，建立了一级反应动力学模型并对模型进行检验。结果表明：在SKI-210催化剂上3种二甲苯相互转化的反应网络符合实验数据；该模型能预测二甲苯异构化反应的产物分布，模型对产物摩尔分数的预测标准偏差在0.0002～0.0152,模型预测值与实测值吻合良好。利用该模型进行模拟分析，考察了反应条件对对二甲苯(PX)收率和选择性的影响，发现在反应温度380℃、反应压力0.6 MPa、质量空速15 h^-1下，PX收率可达24.6%,为工业反应器的操作优化奠定了动力学模型基础。

Kinetic Study of Xylene Isomerization on De-Ethylation Catalyst

 The kinetics of xylene isomerization on SKI-210 de-ethylation C₈ aromatics isomerization catalyst (SKI-210 catalyst for short) was studied in a micro fixed bed reactor. The reaction network consists of the primary isomerization reaction between three xylene isomers and the second disproportionation reaction of xylene. The reaction rate was simulated using Langmuir-Hinshelwood-Hougen-Watson(LHHW) equation, reaction kinetic parameters were obtained through fitting by use of gPROMS software, and a first-order kinetic model was established, and also tested. The results show that the reaction network for the interconversion of three xylenes on SKI-210 catalyst is in line with experimental data; the model can predict the distribution of xylene isomerization products, and the standard deviation for the molar fraction of products predicted by the model is 0.0002—0.0152, from which it can be found that the predicted value of model agrees well with the measured value. In this work, the model was used for simulation analysis and to investigate the impact of reaction conditions on the yield and selectivity of xylene (PX). It is found that PX yield can reach 24.6% at the reaction temperature of 380 ℃, reaction pressure of 0.6 MPa and MHSV of 15 h^-1, providing a kinetic model as the support for the operation optimization of industrial reactors.