FCC反应机理与分子水平动力学模型研究Ⅱ.轻馏分油反应动力学参数的测定

FCC MODELING BASED ON MOLECULAR REACTION DYNAMICS Part 2 Determination of reaction kinetics parameters for catalytic cracking of LCO

以三种不同的轻馏分油为原料,其中二种为催化蜡油生成的轻馏分油,采用三种不同性质的平衡催化剂,在小型催化裂化固定流化床装置上考察馏分油的催化转化反应规律,从催化裂化反应机理出发,把原料及其产物按馏程和化学组成分为链烷烃、环烷烃、烯烃和芳烃等虚拟组分,通过参数估计求取18个反应动力学常数,建立集总动力学模型。结果表明:反应动力学常数反映了催化裂化反应的特征,该模型能较好地拟合试验数据,不仅能预测不同原料的产品分布,而且可以预测汽油和液化气组成,为进一步研究以重质油为原料降低汽油烯烃含量和多产轻烯烃的催化裂化反应作了准备。

Based on the reaction mechanism of FCC, the feedstock and products were classified into suppositional components of paraffin, naphthene, olefin and aromatics according to the molecular kinetic model established in part I.. The behavior of catalytic cracking of three light feeds including two LCO was studied by using a fixed-fluidized bed reactor over three different equilibrium catalysts. Eighteen kinetic parameters of lumping reaction kinetic model were determined with the experimental data. The model simulation results were coincident with the experimental data. The proposed model could not only predict successfully the yield distribution, but also could give more information on the compositions of cracked naphtha and LPG, which provided the basis for further studying the heavy oil FCC to reduce the olefin content in naphtha and to produce more light olefins.