Optimization of Pd Membrane Reactor for  Direct Oxidation of Aromatic Compounds

Milad Rasouli; Sahar Chitsazan; Mohammad Hossein Sayyar; Nakisa Yaghobi; Babak Bozorgi

Milad Rasouli Department of Chemical Engineering, Islamic Azad University, South Tehran Branch, Tehran, Iran ; Department of Petrochemical, Iran Polymer and Petrochemical Institute, P.O.Box: 14965/115, Tehran, Iran
Sahar Chitsazan Department of Chemical Engineering, Islamic Azad University, South Tehran Branch, Tehran, Iran ; Department of Petrochemical, Iran Polymer and Petrochemical Institute, P.O.Box: 14965/115, Tehran, Iran
Mohammad Hossein Sayyar Department of Petrochemical, Iran Polymer and Petrochemical Institute, P.O.Box: 14965/115, Tehran, Iran
Nakisa Yaghobi Department of Petrochemical, Iran Polymer and Petrochemical Institute, P.O.Box: 14965/115, Tehran, Iran
Babak Bozorgi GC Laboratory, National Petrochemical Company, Research and Technology, Tehran, Iran

Keywords: membrane reactor, modeling, Pd membrane, direct oxidation

Abstract

Computational fluid dynamic has already become a widely used and indispensable
design and optimization tool in many technical areas. In the present work, the CFD
simulations have been coupled with complex chemical reactions to model a membrane
tubular reactor which is used to produce phenol from benzene in the vapor phase.
Hydrogen dissociates on the palladium layer and reacts with oxygen to give active
oxygen species, which attack benzene to produce phenol. In principal, reaction occurs in
the surface of palladium and conversion of benzene is increased by changing the length
and diameter of the Pd coated PSS tubes. The reactor length and diameter are two
geometrical factors which are concerned in the present study. Although increasing the
reactor length increase the conversion of benzene to phenol but the concentration of the
phenol start to decrease. Based on the data provided by the experiments, a
mathematical model has been constructed to conduct a simulation which leads us to an
optimum design of a new tubular membrane micro-reactor.

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