abstract |
Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at dehydrogenation conditions, with a catalytic composite comprising a combination of catalytically effective amounts of a platinum or palladium component, a rhodium component, and a lead component with a porous carrier material. A specific example of the catalytic composite disclosed herein is a combination of a platinum or palladium component, a rhodium component, a lead component, and an alkali or alkaline earth component with a porous carrier material, wherein substantially all of the platinum or palladium component and the rhodium component are present therein as the corresponding elemental metals and substantially all of the lead component and the alkali or alkaline earth component are present therein in an oxidation state above the elemental metal, and wherein the composite contains about 0.01 to about 2 wt. % platinum or palladium, about 0.01 to about 2 wt. % rhodium, about 0.1 to about 5 wt. % alkali metal or alkaline earth metal, and lead in an amount sufficient to result in an atomic ratio of lead to platinum or palladium of about 0.05:1 to about 0.9:1. |