Claims
- 1. A process for producing a high Viscosity Index (VI) lubricant having a VI of at least 125 from a waxy hydrocarbon feed having a wax content of at least 40%, which comprises catalytically dewaxing waxy paraffins present in the feed primarily by isomerization, in the presence of hydrogen and in the presence of a low acidity large pore zeolite isomerization catalyst having a ratio of SiO.sub.2 /Al.sub.2 O.sub.3, as synthesized, of at least 50:1, an alpha value of not more than 20 and further comprises a noble metal hydrogenation component wherein the catalyst is prepared in the absence of boron.
- 2. The process of claim 1 wherein the large-pore zeolite possesses at least one pore channel of 12-membered oxygen rings.
- 3. The process of claim 1, wherein the large pore zeolite is zeolite beta.
- 4. The process of claim 1, wherein the ratio of SiO.sub.2 /Al.sub.2 O.sub.3 is at least 200:1.
- 5. The process of claim 4, wherein the ratio of SiO/Al.sub.2 O.sub.3 is at least 600:1.
- 6. The process of claim 1, in which the noble metal of the hydrogenation component is Pt or Pd.
- 7. The process of claim 1, in which the noble metal content of the hydrogenation catalyst is in the range from about 0.1 to 2 wt %.
- 8. The process of claim 1 in which the feed comprises a waxy hydrocarbon feed having a wax content of at least 50 wt % and an aromatic content of least than 25 wt %.
- 9. The process of claim 1 wherein the feedstock is selected from the group consisting of a slack wax, deoiled wax, wax from Fischer-Tropsch process, petrolatum, vacuum gas oil, or a raffinate from solvent extraction of a vacuum distillate.
- 10. The process of claim 1, in which the process is carried out in the presence of hydrogen.
- 11. The process of claim 10, in which the wax conversion is from 40 to 90 wt. % of the wax contained in the feed.
- 12. The process of claim 9, in which the wax conversion is from 50 to 80 wt % based on the feed.
- 13. The process of claim 1, wherein the effluent has a pour point which ranges from about 30.degree. to about 100.degree. F.
- 14. The process of claim 1, wherein conditions include a hydrogen partial pressure ranging from 600 to 3000 psig and a temperature from 550.degree. to 800.degree. F.
- 15. The process of claim 1, wherein the preferred range of VI is from 130 to 150.
- 16. The process of claim 1 in which the effluent is subjected to further dewaxing to achieve target pour point, with a yield loss during dewaxing of not more than 15 wt %.
- 17. The process of claim 16, in which dewaxing is accomplished by either solvent or catalytic means.
- 18. The process of claim 1, in which the effluent is hydrotreated by contacting it with a catalyst comprising a metal hydrogenation component on an amorphous, porous support material at a pressure in the range from about 500 to about 3000 psig, a reaction temperature in the range from about 500.degree. F. to about 800.degree. F., a space velocity which is in a range from about 0.1 to about 10 LHSV, and a once-through hydrogen circulation rate which extends from about 1000 SCF/B to about 10,000 SCF/B, in order to improve the thermal and oxidative stability of the lubricant.
- 19. A process for producing a high Viscosity Index (VI) lubricant having a VI of a least 125 from a waxy hydrocarbon feed having a wax content of at least 40 wt %, the process comprising the following steps:
- (a) hydrocracking of the feed in order to reduce its nitrogen as well as to remove napthenic and aromatic components, thereby improving VI, the hydrocracking process comprising contacting the feed with a catalyst composed of a metal hydrogenation component on an acidic support;
- (b) catalytically dewaxing waxy paraffins present in the feed primarily by isomerization, in the presence of hydrogen and in the presence of a low acidity large pore zeolite isomerization catalyst having a ratio of SiO.sub.2 /Al.sub.2 O.sub.3, as synthesized, of at least 50:1, the catalyst possessing an alpha value of not more than 20 and further comprising a noble metal hydrogenation component wherein the catalyst is prepared in the absence of boron.
- 20. The process of claim 19 wherein the large-pore zeolite possesses at least one pore channel of 12-membered oxygen rings.
- 21. The process of claim 19, wherein the large pore zeolite is zeolite beta.
- 22. The process of claim 19, wherein the ratio of SiO.sub.2 /Al.sub.2 O.sub.3 is at least 200:1.
- 23. The process of claim 21, wherein the ratio of SiO.sub.2 /Al.sub.2 O.sub.3 is at least 600:1.
- 24. The process of claim 19 wherein the feedstock is selected from the group consisting of a slack wax, deoiled wax, wax from Fischer-Tropsch process, petrolatum, vacuum gas oil, and a raffinate from solvent extraction of a vacuum distillate.
- 25. The process of claim 19 wherein conditions include a hydrogen partial pressure ranging from 600 to 3000 psig and a temperature from 550.degree. to 800.degree. F.
- 26. The process of claim 19, wherein the preferred range of VI is from 130 to 150.
- 27. The process of claim 19 in which the effluent of step (b) is subjected to further dewaxing to achieve target pour point, with a loss during dewaxing of not more than 15 wt %.
- 28. The process of claim 19, in which the effluent of step (b) is hydrotreated by contacting it with a catalyst comprising a metal hydrogenation component on an amorphous porous support material at a pressure in the range from about 500 to about 3000 psig, a reaction temperature in the range from about 500.degree. F. to about 800.degree. F., a space velocity which is in a range from about 0.1 to about 10 LHSV, and a once-through hydrogen circulation rate which extends from about 1000 SCF/B SCF/B to about 10,000 SCF/B, in order to improve the thermal and oxidative stability of the lubricant.
- 29. A process for producing a high Viscosity Index (VI) lubricant having a VI of at least 120 from a waxy hydrocarbon feed having a wax content of at least 30 wt %, the process employing two catalysts operating synergistically, and comprising the following steps:
- (a) hydrocracking of the feed in order to reduce its nitrogen content as well as to remove naphthenic and aromatic components, thereby improving VI, the hydrocracking process comprising contacting the feed with a catalyst composed of a metal hydrogenation component on an acidic support;
- (b) catalytically dewaxing waxy paraffins present in the feed primarily by isomerization, in the presence of hydrogen and in the presence of a low acidity large pore zeolite isomerization catalyst having a ratio of SiO.sub.2 /Al.sub.2 O.sub.3, as synthesized, of at least 50:1, the catalyst possessing an alpha value of not more than 20 and further comprising a noble metal hydrogenation component wherein the catalyst is prepared in the absence of boron;
- (c) subjecting the effluent of the initial catalytic dewaxing step to a second catalytic dewaxing step in which the effluent is contacted with a constrained intermediate pore crystalline material, which contains a metal hydrogenation dehydrogenation component.
CROSS-REFERENCE TO RELATED APPLICATIONS
The instant application is a continuation-in-part of Ser. No. 08/017,955 now abandoned. The instant application is also a continuation-in-part of Ser. No. 08/017,949 now abandoned. Ser. No. 08/017,955 now abandoned is incorporated by reference in the instant application. Corresponding European Patent No. 464,547A1, (a patent which specifies the use of low acidity zeolite beta for wax isomerization) is also incorporated by reference. The instant application is related to co-pending application Ser. No. 08/303,091 in which two dewaxing catalysts operate synergistically to produce a lubricant of high Viscosity Index. It is also related to Ser. No. 08/329,914, which is concerned with isomerizing petroleum waxes using large pore zeolites of small crystallite size.
US Referenced Citations (7)
Related Publications (1)
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017949 |
Feb 1993 |
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Continuation in Parts (1)
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017955 |
Feb 1993 |
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