Numerical analysis of the optimal catalyst distribution in created unsteady state conditions

Subject Areas : Journal of the Iranian Chemical Research

Yacine Benguerba ¹ , Brahim Djellouli ² , Lemnouer Chibane ³ , Lahcene Bencheikh ⁴

1 - Laboratoire de Génie des Procédés Chimiques, Université Ferhat Abbas Sétif, 19000, Sétif, Algérie
2 - Laboratoire de Génie des Procédés Chimiques, Université Ferhat Abbas Sétif, 19000, Sétif, Algérie
3 - Laboratoire de Génie des Procédés Chimiques, Université Ferhat Abbas Sétif, 19000, Sétif, Algérie
4 - Laboratoire de Génie des Procédés Chimiques, Université Ferhat Abbas Sétif, 19000, Sétif, Algérie

Received: 2009-12-03 Accepted : 2009-12-27 Published : 2009-07-05

Keywords: Unsteady state, Optimal catalyst distribution, Forced perturbation, Temperature modulation, Concentration modulation,

Abstract :

The determination of the optimal distribution of the catalytic activity profile, whichmaximizes the catalytic effectiveness, in created unsteady state conditions, is analyzed andtreated numerically for the case of a simple reaction. It was proven that the modulation, of thetemperature and the reactant concentration of the external bulk fluid, leads to a considerableincrease of the catalytic effectiveness. The optimal active element distribution is a Dirac- δfunction i.e. all the catalyst must be deposited at a specific distance from the center of thecatalytic pellet. It was shown that this optimal position changes with time in a sinusoidal manner.This purpose can be achieved by the use of ultrasounds to artificially control the activity profile.

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