GALLIUM CONTAINING HYBRID CATALYSTS FOR THE AROMATIZATION OF NORMAL-BUTANE

The enhancement of the aromatization activity of the gallium containing hybrid catalysts may partly be ascribed to the formation, upon reduction, of gallium species having a lower oxidation state and their subsequent transfer/redistribution within the catalyst mass. Within the hybrid catalysts which contains the cocatalyst prepared by evaporation of a gallium salt/colloidal silica mixture, some transfer of gallium onto the external surface of the zeolite particles effectively occurs. However, the high aromatization performance of such a hybrid catalyst results mainly from the physical presence of the cocatalyst which exhibits strong hydrogen spillover effects.