Patent AU-764183-B2 (AU)
Title: Improved fischer-tropsch activity for "non-promoted" cobalt-on-alumina catalysts
Inventor: SINGLETON ALAN H
IPC: B01J23/83
Filed: 1999-05-26
Granted: 2003-08-14
Abstract: 1. A cobalt catalyst for hydrocarbon synthesis on Fischer-Tropsch, said cobalt catalyst comprising cobalt supported on a gamma-alumina support, wherein said cobalt catalyst is not promoted with any noble metals, rhenium, technetium or titanium supported on said a gamma-alumina support, said gamma-alumina support includes a dopant in an amount effective for increasing the activity of said cobalt catalyst for said hydrocarbon synthesis. 2. The cobalt catalyst of claim 1, wherein said amount of titanium dopant is an amount effective to render said cobalt catalyst at least 60% as active as a promoted catalyst which is identical to said cobalt catalyst except that said promoted catalyst is promoted with ruthenium in a ruthenium to cobalt weight ratio of 1: 40. 3. The cobalt catalyst of claim 2, wherein said amount of said titanium dopant is an amount effective to render said cobalt catalyst at least 70% as active as said promoted catalyst. 4. The cobalt catalyst of claim 3, wherein said amount of said titanium dopant is an amount effective to render said cobalt catalyst at least 80% as active as said promoted catalyst. 5. The cobalt catalyst of claim 1, wherein said amount of said titanium dopant, expressed as elemental titanium, is at least 500 ppm by weight of the total weight of said gamma-alumina support. 6. The cobalt catalyst of claim 1, wherein said amount of said titanium dopant, expressed as elemental titanium, is in the range of from about 800 to about 2000 ppm by weight of the total weight of said gamma-alumina support. 7. The cobalt catalyst of claim 1, wherein said amount of said titanium dopant, expressed as elemental titanium, is about 1000 ppm by weight of the total weight of said gamma-alumina support. 8. The cobalt catalyst of claim 1, wherein said cobalt catalyst is an activated catalyst which has been reduced in the presence of hydrogen and at a water vapor partial pressure effective to increase said activity of said cobalt catalyst. 9. The cobalt catalyst of claim 1, wherein said cobalt catalyst is promoted with at least one of potassium and lanthana. 10. The cobalt catalyst of claim 1, wherein said gamma-alumina support is produced from synthetic boehmite and said dopant is added to said gamma-alumina support prior to the crystallization of said synthetic boehmite. 11. A process for producing a hydrocarbon comprising the step of reacting a synthesis gas in the presence of a cobalt catalyst wherein said cobalt catalyst comprises cobalt supported on a gamma-alumina support; said cobalt catalyst is not promoted with any noble metals, rhenium, technetium or titanium supported on said gamma-alumina support and said gamma-alumina support includes a dopant in an amount effective for increasing the activity of said cobalt catalyst for said hydrocarbon synthesis on Fischer-Tropsch. 12. The process of claim 11, wherein said amount of said titanium dopant is an amount effective to render said cobalt catalyst at least 60% as active for said hydrocarbon synthesis as a promoted catalyst which is identical to said cobalt catalyst, except that said promoted catalyst is promoted with ruthenium in ruthenium to cobalt weight ratio of 1: 40. 13. The process of claim 12, wherein said amount of said titanium dopant is an amount effective to render said cobalt catalyst at least 70% as active as said promoted catalyst. 14. The process of claim 12, wherein said amount of said titanium dopant is an amount effective to render said cobalt catalyst at least 80% as active as said promoted catalyst. 15. The process of claim 11, wherein said amount of said titanium dopant, expressed as elemental titanium, is at least 500 ppm by weight of the total weight of said gamma-alumina support. 16. The process of claim 11, wherein said amount of said titanium dopant, expressed as elemental titanium, is in the range of from about 800 to about 2000 ppm by weight of the total weight of said gamma-alumina support. 17. The process of claim 11, wherein said amount of said titanium dopant, expressed as elemental titanium, is about 1000 ppm by weight of the total weight of said gamma-alumina support. 18. The process of claim 11 further comprising the step, prior to said step of reacting, of activating said cobalt catalyst by reducing said cobalt catalyst in the presence of hydrogen and at a water vapor partial pressure effective to increase said activity of said cobalt catalyst. 19. The process of claim 18, wherein said water vapor partial pressure is in the range of from 0 to about 0.1 atmospheres. 20. A cobalt catalyst for hydrocarbon synthesis comprising cobalt supported on a gamma-alumina support, wherein said cobalt catalyst is not promoted with any noble metals, rhenium, technetium or titanium supported on said gamma-alumina support, said gamma-alumina support includes an amount of a titanium dopant, and said cobalt catalyst has been reduced in the presence of hydrogen at a water vapor partial pressure effective to increase the activity of said cobalt catalyst for said hydrocarbon synthesis. 21. The cobalt catalyst of claim 20, wherein said gamma-alumina support includes an amount of a titanium dopant of at least 500 ppm by weight, expressed as elemental titanium, of the total weight of said gamma-alumina support. 22. The cobalt catalyst of claim 21, wherein said amount of said titanium dopant, expressed as elemental titanium, is in the range from about 800 to about 2000 ppm by weight of the total weight of said gamma-alumina support. 23. The cobalt catalyst of claim 21, wherein said gamma-alumina support is produced from synthetic boehmite and said dopant is added to said gamma-alumina support prior to the crystallization of said synthetic boehmite. 24. A process for hydrocarbon synthesis comprising the following steps: (a) reducing a cobalt catalyst in the presence of hydrogen and at a water vapor partial pressure effective to increase the activity of said cobalt catalyst for said hydrocarbon synthesis, wherein said cobalt catalyst comprising cobalt supported on a gamma-alumina support, said gamma-alumina support includes an amount of a titanium dopant, and (b) reacting a synthesis gas in the presence of said cobalt catalyst, wherein said cobalt catalyst is not promoted with any noble metals, rhenium, technetium or titanium supported on said gamma-alumina support. 25. The process of claim 24, wherein said gamma-alumina support includes an amount of a titanium dopant of at least 500 ppm by weight, expressed as elemental titanium, of the total weight of said gamma-alumina support. 26. The process of claim 25, wherein said amount of said titanium dopant, expressed as elemental titanium, is in the range of from about 800 to about 2000 ppm by weight of the total weight of said gamma-alumina support. 27. The method of improving the activity of a cobalt catalyst for hydrocarbon synthesis, comprising said cobalt supported on said gamma-alumina support, said method comprising the step of including in said support a titanium dopant in an amount, expressed as elemental titanium, of at least 500 ppm by weight of the total weight of said alumina support.