Dehydrocyclization with an acidic multimetallic catalytic composite

Abstract

Dehydrocyclizable hydrocarbons are converted to aromatics by contacting them at dehydrocyclization conditions with an acidic multimetallic catalytic composite comprising a combination of catalytically effective amounts of a platinum or palladium component, a rhodium component, a cobalt component, and a halogen component with a porous carrier material. In a preferred embodiment, the catalytic composite also contains a catalytically effective amount of a Group IVA metallic component. The platinum or palladium, rhodium, cobalt and halogen components are present in the multimetallic catalyst in amounts respectively, calculated on an elemental basis, corresponding to about 0.01 to about 2 wt. % platinum or palladium metal, about 0.01 to about 2 wt. % rhodium, about 0.05 to about 5 wt. % cobalt, and about 0.1 to about 3.5 wt % halogen. Moreover, the catalytically active sites induced by these metallic components are uniformly dispersed throughout the porous carrier material and these metallic components are present in the catalyst in carefully controlled oxidation states. A specific example of the dehydrocyclization method disclosed herein is a method for converting a feed mixture of n-hexane and n-heptane to a product mixture of benzene and toluene which involves contacting the feed mixture and a hydrogen stream with the acidic multimetallic catalyst disclosed herein at dehydrocyclization conditions.