KINETIC-STUDY OF N-BUTANE AROMATIZATION ON ZSM-5 AND GALLIUM BEARING ZSM-5 CATALYSTS

The apparent activation energies and pre-exponential factors for n-butane conversion over "pure" ZSM-5 zeolite and two gallium bearing ZSM-5 catalysts have been determined. Although these three catalysts give the same value for the activation energy (100 kJ/mol), the values of the pre-exponential factor exhibit a sequence which is coincident to that of the aromatization performance: parent zeolite < Cyclar-type catalyst < hybrid catalyst. In several aspects of the aromatization activity and selectivity, the hybrid catalyst behaves differently from the Cyclar-type catalyst.