基于结构导向集总的催化重整分子水平反应动力学模型

为了从分子水平揭示催化重整反应过程的转化规律,基于结构导向集总理论,设计了14个结构单元来描述催化重整反应体系中的312种分子。根据催化重整反应机理,制定了包括裂化、异构化、环化、芳构化等反应的78条反应规则来描述催化重整过程的分子反应行为,构建了包含1628个反应的催化重整反应网络。结合反应动力学常数计算,建立了分子尺度的催化重整反应动力学模型,并采用改进的Runge-Kutta法进行求解。通过与不同工艺条件下的实验数据比较,验证了模型的可靠性。利用所建模型分析了反应温度、压力、空速等操作条件对重整反应过程的影响规律,揭示反应器中芳烃、环烷烃、异构烷烃和正构烷烃等烃类分子的转化规律,获得催化重整产物分子组成及其沿反应器的分布规律。该模型可以指导催化重整装置实现芳烃收率和液体收率的双目标优化。

Reaction Kinetic Model for Catalytic Reforming Based on Structure Oriented Lumping

14 structural units were designed to describe 312 molecules in the catalytic reforming reaction system based on the structure oriented lumping theory, in order to reveal the transformation law of catalytic reforming reaction at the molecular level. According to the mechanism of catalytic reforming reaction, 78 reaction rules including cracking, isomerization, cyclization and aromatization were formulated to describe the molecular reaction behavior of catalytic reforming process. A catalytic reforming reaction network consisting of 1628 reactions was constructed. A molecular-scale kinetic model of catalytic reforming reaction was established by calculating the kinetic constants of the reaction, and the modified Runge Kutta method was used to solve the model. The reliability of the model is verified by comparing with the experimental data under different process conditions. The model can be used to analyze the effects of operating conditions such as temperature, pressure and space velocity on the reforming process, to reveal the transformation rules of hydrocarbon molecules such as aromatics, cycloalkanes, isoparaffins and n-paraffins in the reactor, and obtain the molecular composition of catalytic reforming products and their distribution along the reactor. The model can guide the catalytic reforming unit to achieve the two objective optimization of aromatics yield and liquid yield.