Claims
- 1. In a process for the dehydrogenation of a hydrocarbon selected from the group consisting of propane and butane in the presence of a catalyst comprising platinum and a carrier material wherein said dehydrogenation is conducted at severe operating conditions which promote rapid deactivation of said catalyst including the agglomeration of said platinum on said carrier material and the deposition of coke on said catalyst, the improvement which comprises the steps of contacting said catalyst comprising platinum and a carrier material having coke deposited thereon with an oxygen containing gas to remove said coke by combustion; contacting said catalyst having coke removed therefrom with a drying gas having a temperature in a range of from about 800.degree. F. (426.degree. C.) to about 1100.degree. F. (593.degree. C.) and an oxygen concentration from about 21 to about 39 mole percent until said catalyst has a water concentration of less than about 1 weight percent; contacting said catalyst comprising platinum and a carrier material having a water concentration of less than about 1 weight percent with a re-dispersion gas comprising chlorine and having an oxygen concentration from about 21 to about 39 mole percent to re-disperse platinum on said catalyst; contacting the resulting catalyst having re-dispersed platinum in a reduction zone with a hydrogen-rich gas at a temperature from about 700.degree. F. (371.degree. C.) to about 1100.degree. F. (593.degree. C.) and a pressure from about 5 psig (34.5 kPa gauge) to about 125 psig (862 kPa gauge); and recovering reconditioned catalyst from said reduction zone.
- 2. The process of claim 1 wherein said catalyst is continuously withdrawn and delivered to a dehydrogenation zone.
- 3. The process of claim 1 wherein said catalyst contains a component selected from the group consisting of cesium, rubidium, potassium, sodium, lithium, calcium, strontium, barium and magnesium.
- 4. The process of claim 1 wherein said catalyst contains a carrier material which comprises alumina.
CROSS REFERENCE TO RELATED APPLICATION
The present application is a continuation-in-part of co-pending application Ser. No. 638,952 filed on Jan. 9, 1991, now U.S. Pat. No. 5,087,792, all of which is incorporated by reference.
US Referenced Citations (12)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
638952 |
Jan 1991 |
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