Applied Catalysis A: General, Vol.489, 226-234, 2015
Mathematical modeling and parametric study of a dehydrogenation catalyst decoking process
The present study provides a dynamic mathematical model for a regeneration process of coked catalysts in a multi-tube fixed-bed reactor. Mass and energy conservation laws are applied to predict the temperature variation of gas and solid phases along the reactor length in two main stages: heating and coke burning. The kinetics of decoking is obtained by fitting the data taken from a pilot-scale reactor. The model results are compared with the experimental data taken from both a pilot-scale and a commercial-scale plant. The effect of operating parameters, including inlet gas flow rate, temperature, and composition on the reactor performance is studied. Controlling the O-2 concentration is the best strategy to prevent the catalyst sintering. In order to reduce the regeneration process duration, two strategies are examined: constant and stepwise rising trend of inlet O-2 concentration. Using the inlet O-2 molar-fraction of 5.5% reduces the regeneration duration by about 4h. (C) 2014 Elsevier B.V. All rights reserved.