Application of Percolation Theory in the Modeling of Catalyst Deactivation in a Fixed Bed Reactor of Methanol to Light Olefin Catalytic Conversion



1 Department of Chemical Engineering, Faculty of Engineering, Persian Gulf University, Bushehr, I.R. IRAN

2 Faculty of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran,, I.R. IRAN


A reactor model for prediction of the deactivation behavior of MTO’s porous catalyst in a fixed bed reactor is developed. Percolation theory was used to predict the effect of coking on molecular transport in the porous structure of SAPO-34.The predicted loss in catalyst activity with time-on-stream was in very good agreement with the experimental data. The resulting coke deposition along the length of reactor suggested a moving reaction front in thecatalyst bed of reactor at the operating experimental conditions of 1 h-1 and 723 K for methanol space velocity and inlet temperature, respectively. Effects of space time, coordination of model of porous network, and effective diffusivity of component in reaction mixture on the reactor performance are presented.  


Main Subjects

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