Reaction Zone Evolution of Catalytic Pathways for Propane Aromatization in a Large-Scale Turbulent Fluidized Bed

Abstract

CFD simulations are conducted to predict the axial reaction zone evolution of catalytic pathways for propane aromatization in a large-scale turbulent fluidized bed. A transport–reaction coupled CFD model is established for the propane aromatization reactor. The results show that lower propane inlet velocity, higher propane inlet temperature (600 °C), and an appropriate outlet pressure (1.25–1.50 atm) favor aromatics yield. Increasing propane inlet temperature or outlet pressure increases the aromatics-to-alkanes ratio, indicating that the reaction gradually shifts toward propane aromatization via alkenes, whereas propane inlet velocity has little influence on the aromatics-to-alkanes ratio. Further analysis based on product-yield gradient distributions reveals distinct axial evolution characteristics of the reaction pathways, on the basis of which the bed is divided into alkene-formation-dominated zone, aromatization-dominated zone, and reaction-completion zone. This work aims to clarify the effects of operating parameters on competing reaction pathways and reaction zone evolution behavior.