Claims
- 1. A method for dehydrogenating a naphthene hydrocarbon comprising contacting the hydrocarbon, at dehydrogenation conditions, with a nonacidic catalytic composite consisting essentially of a porous carrier material containing, on an elemental basis, about 0.01 to about 2 wt. % platinum group metal, about 0.05 to about 5 wt. % cobalt, and about 0.01 to about 5 wt. % bismuth; wherein the platinum group metal, catalytically available cobalt and bismuth are uniformly dispersed throughout the porous carrier material; wherein substantially all of the platinum group metal is present in the elemental metallic state; and wherein substantially all of the catalytically available cobalt is present in the elemental metallic state or in a state which is reducible to the elemental metallic state under dehydrogenation conditions or in a mixture of these states.
- 2. A method as defined in claim 1 wherein the naphthene hydrocarbon is admixed with hydrogen when it contacts the catalytic composite.
- 3. A method as defined in claim 1 wherein the platinum group metal is platinum.
- 4. A method as defined in claim 1 wherein the platinum group metal is iridium.
- 5. A method as defined in claim 1 wherein the platinum group metal is rhodium.
- 6. A method as defined in claim 1 wherein the platinum group metal is palladium.
- 7. A method as defined in claim 1 wherein the naphthene hydrocarbon is cyclohexane.
- 8. A method as defined in claim 1 wherein the porous carrier material is a refractory inorganic oxide.
- 9. A method as defined in claim 8 wherein the refractory inorganic oxide is alumina.
- 10. A method as defined in claim 2 wherein the dehydrogenation conditions include a temperature of 700 to about 1200.degree. F., a pressure of 0.1 to 10 atmospheres, a LHSV of 1 to 40 hr..sup.-1, and a hydrogen to hydrocarbon mole ratio of about 1:1 to about 20:1.
- 11. A method as defined in claim 1 wherein the composite contains on an elemental basis, about 0.05 to about 1 wt. % platinum group metal, about 0.1 to about 2.5 wt. % cobalt and about 0.05 to about 1 wt. % bismuth.
- 12. A method as defined in claim 1 wherein the metals content of the catalytic composite is adjusted so that the atomic ratio of bismuth to platinum group metal is about 0.1:1 to about 2:1 and the atomic ratio of cobalt to platinum group metal is about 0.1:1 to about 66:1.
- 13. A method as defined in claim 1 wherein substantially all of the bismuth is present therein in an oxidation state above that of the elemental metal.
- 14. A method as defined in claim 13 wherein substantially all of the bismuth is present in the catalytic composite as bismuth oxide or bismuth aluminate.
- 15. A method as defined in claim 2 wherein substantially all of the catalytically available cobalt contained in the composite is present in the elemental metallic state after the method is started-up and linedout at dehydrogenation conditions.
- 16. A method for dehydrogenating a naphthene hydrocarbon comprising contacting the hydrocarbon, at dehydrogenation conditions, with a nonacidic catalytic composite consisting essentially of a porous carrier material containing, on an elemental basis, about 0.01 to about 2 wt. % platinum group metal, about 0.05 to about 5 wt. % cobalt, about 0.1 to about 5 wt. % alkali metal or alkaline earth metal, and about 0.01 to about 5 wt. % bismuth; wherein the platinum group metal, catalytically available cobalt, bismuth and alkali metal or alkaline earth metal are uniformly dispersed throughout the porous carrier material; wherein substantially all of the platinum group metal is present in the elemental metallic state; wherein substantially all of the catalytically available cobalt is present in the elemental metallic state or in a state which is reducible to the elemental metallic state under dehydrogenation conditions or in a mixture of these states; and wherein substantially all of the alkali metal or alkaline earth metal is present in an oxidation state above that of the elemental metal.
- 17. A method as defined in claim 16 wherein the porous carrier material is a refractory inorganic oxide.
- 18. A metod as defined in claim 17 wherein the refractory inorganic oxide is alumina.
- 19. A method as defined in claim 16 wherein the alkali metal or alkaline earth metal is potassium.
- 20. A method as defined in claim 16 wherein the alkali metal or alkaline earth metal is lithium.
- 21. A method as defined in claim 16 wherein the naphthene hydrocarbon is cyclohexane.
- 22. A method as defined in claim 16 wherein the composite contains, on an elemental basis, about 0.05 to about 1 wt. % platinum group metal, about 0.1 to about 2.5 wt. % cobalt, about 0.05 to about 1 wt. % bismuth, and about 0.25 to about 3.5 wt. % alkali metal or alkaline earth metal.
- 23. A method as defined in claim 16 wherein the metals contents thereof is adjusted so that the atomic ratio of bismuth to platinum group metal is about 0.1:1 to about 2:1, the atomic ratio of alkali metal or alkaline earth metal to platinum group metal is about 5:1 to about 100:1 and the atomic ratio of cobalt to platinum group metal is about 0.1:1 to 66:1.
- 24. A method as defined in claim 16 wherein the naphthene hydrocarbon is admixed with hydrogen when it contacts the catalytic composite.
- 25. A method as defined in claim 24 wherein the dehydrogenation conditions include a temperature of about 700 to about 1200.degree. F., a pressure of about 0.1 to about 10 atmospheres, an LHSV of about 1 to 40 hr..sup.-1, and a hydrogen to hydrocarbon mole ratio of about 1:1 to about 20:1.
- 26. A method as defined in claim 24 wherein the contacting is performed in the presence of water or a water-producing substance in an amount corresponding to about 1 to about 1000 wt. ppm. based on hydrocarbon charge.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of my prior, copending application Ser. No. 718,310 filed Aug. 27, 1976, now U.S. Pat. No. 4,079,097, Mar. 14, 1978, and which is in turn a continuation-in-part of my prior application Ser. No. 602,935 filed Aug. 8, 1975 and issued Sept. 21, 1976 as U.S. Pat. No. 3,981,795. All of the teachings of these prior applications are specifically incorporated herein by reference.
US Referenced Citations (3)
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3655747 |
Sennewald et al. |
Apr 1972 |
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3759823 |
Davies et al. |
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Divisions (1)
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Number |
Date |
Country |
Parent |
718310 |
Aug 1976 |
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Continuation in Parts (1)
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Number |
Date |
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Parent |
602935 |
Aug 1975 |
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