Dehydrocyclization with an acidic multimetallic catalytic composite

Abstract

Dehydrocyclizable hydrocarbons are converted to atomatics 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 rhenium component, a tin component, and a halogen component with a porous carrier material. The platinum or palladium, rhodium, rhenium, tin 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, about 0.01 to about 2 wt. % rhodium, about 0.01 to about 2 wt. % rhenium, about 0.01 to about 5 wt. % tin, 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 such that substantially all of the platinum or palladium, rhodium and rhenium components are in the elemental metallic state and substantially all of the tin is in an oxidation state above that of the elemental metal. 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.