Ali Izadbakhsh

A mathematical reactor model for the prediction of the transient performance of a methanol-to-olefin fixed bed reactor is applied to simulate the adopted experimental data. The effect of coking on molecular transport in the porous structure of SAPO-34 as catalyst has been simulated using percolation theory. The porous structure of catalyst particles was modeled by using a Bethe network. Thermal effects of the reaction were considered in the model. The predicted profiles of concentrations with time-on-stream were in very good agreement with the experimental data before the steep drop of product concentrations appears in the reactor effluent. The resulting coke deposition and gas temperature profiles along the length of reactor suggested a reaction front moving toward the outlet of the fixed bed reactor operating under the experimental conditions. The predicted concentration profiles of the main species of the reaction inside catalyst particles and calculated Thiele modulus proposed that their overall rates are diffusion-controlled. Simulation results at high space velocities represented a reasonable trend of temperature and concentrations variation.