EA-8402分子筛催化剂上乙苯/乙烯烷基化反应的宏观动力学研究

MACRO-KINETICS OF ETHYLBENZENE/ETHYLENE ALKYLATION OVER EA-8402 ZEOLITE CATALYSTS

用磁驱动内循环无梯度反应器在常压、593～653K 范围内考察了 EA-8402分子筛催化剂催化乙苯/乙烯烷基化合成二乙苯的动力学规律,建立了相应的宏观动力学模型:(-γ_(EB))=1654.47exp(-5884/T)p_(Et)^(0.256)p_(EB)^(0.522)通过对中试装置反应器进行的工况模拟计算,验证了模型的可靠性和适用范围。

The kinetic performance of the directional alkylation of ethylbenzene/ethylene to para-diethylbenzene(purity>95%)over EA-8402 zeolite catalysts was investigated in a magnetic-driving.internal recycle,gradientless reactor at a range of 593-653 K under normal pressure.Based on the thermodynamic calculation and product composition analysis,it was assumed that the reaction system includes alkylation and disproportionation of ethylbenzene only,and was affirmed that the concept of“pseudo-steday reaction rate”is appropriate to the data treatment.The macro-kinetic models were expressed as exponential form as follows: (-r_(EB))=1654.47exp(-5884/T)p_(Et)^(0.256)p_(EB)^(0.522) r_B=5.265×10~9exp(-17366/T)p_(Et)^(-0.391)p_(EB)^(1.135) r_(DEB)(?)383.67exp(-4696/T)p_(Et)^(0.441)p_(EB)^(0.454)(T<645K) 1.860×10^(-4)exp(4681/T)p_(Et)^(0.441)p_(EB)^(0.454)(T>645K) The relative deviations of model predictions to experimental data are within 0.3 to 9%. To demonstrate the validity of models,simulation analysis of a pilot reactor(productive capacity:200 ton pDEB/y)was made.It was shown that the computed values of axial temperature distribution by using the kinetic models are consistent with those measured in the pilot plant,and, except for the initial and final stage of catalyst life,the conversion of ethylbenzene and selectivity of diethylbenzene agree well with the measured values during the stable stage of catalyst activity.