Pore plugging effects on the performance of ZSM-5 catalyst in MTP reaction using a discrete model

摘要

Coke is an important medium for connecting reaction and regeneration of the methanol to propylene process on the ZSM5 catalyst.Coke grows in the meso and macro pores,it gradually worsens the diffusion inside the catalyst particle.Furthermore,pore plugging is inevitable which causes the deactivation of ZSM5 catalyst.However,current continuum model cannot reflect the changes in pore structure with clear physical concepts.A discrete model that is verified by the carbon deposition experiments is introduced to indicate the behavior of pore plugging effects.Results show that the pore plugging has a significant effect on the performance of the catalyst.The time varying profile of effectiveness factor is obtained,indicating a regular reduction with the increase of the pore plugging effect.Spatial distributions of pore size that would significantly enhance the plugging effect are also identified.