Claims
- 1. A process for producing middle distillate fuel products from a paraffin wax, which process comprises (a) contacting the wax with hydrogen in a hydroisomerization zone in the presence of a fluorided Group VIII metal-on-alumina catalyst to convert from about 50 to about 95 weight percent therein of the 700.degree. F..sup.+ material present in the wax thereby maximizing the production of middle distillate fuel product; said catalyst having (i) a bulk fluoride concentration ranging from about 2 to about 10 weight percent, wherein the fluoride concentration is less than about 3.0 weight percent at the outer surface layer to a depth less than one one hundredth of an inch, provided the surface fluoride concentration is less than the bulk fluoride concentration; (ii) an aluminum fluoride hydroxide hydrate level greater than about 60 where an aluminum fluoride hydrate level of 100 corresponds to the X-ray diffraction peak height at 5.66 .ANG. for a Reference Standard; and (iii) a N/Al ratio less than about 0.005 and (b) recovering a middle distillate product and a bottoms product having an initial boiling point above 700.degree. F.
- 2. The process of claim 1 wherein said Group VIII metal is platinum.
- 3. The process of claim 1 wherein said catalyst contains about 0.1 to about 2 weight percent platinum.
- 4. The process of claim 3 wherein the catalyst has an aluminum fluoride hydroxide hydrate level of at least 80.
- 5. The process of claim 4 wherein at least a portion of the 700.degree. F..sup.+ bottoms product is recycled to the hydroisomerization zone.
- 6. The process of claim 5 wherein from about 85 wt % to about 90 wt % of the 700.degree. F..sup.+ material present in the feed to the hydroisomerization zone is converted therein.
- 7. The process of claim 6 wherein the catalyst has an aluminum fluoride hydrate level of at least about 100 and a fluoride concentration on the outer surface of less than about 1.0 weight percent.
- 8. The process of claim 7 wherein the catalyst contains a fluoride concentration in the range of about 5 to 8 weight percent, N/Al ratio less than about 0.002 and a fluoride concentration on the outer surface less than about 0.5 weight percent.
- 9. The process of claim 8 wherein said wax is a petroleum slack wax and said wax is hydrotreated to remove nitrogen and sulfur compounds prior to its introduction to the hydroisomerization zone.
- 10. The process of claim 3 wherein at least a portion of the 700.degree. F.+ product is fractionated and dewaxed to produce a lubricating oil boiling in the range of about 650.degree. F. to about 950.degree. F.
- 11. The process of claim 4 wherein at least a portion of the 700.degree. F..sup.+ bottoms product is sent to a second hydroisomerization zone containing the catalyst described for use in the first hydroisomerization for contact with hydrogen and wherein the effluent from the second isomerization zone is fractionated into a light ends fraction boiling below about 700.degree. F., a lubricating oil fraction boiling in the range of about 700.degree. F. to 950.degree. F. and a bottoms fraction having an initial boiling point above about 950.degree. F.
- 12. The process of claim 11 wherein the 950.degree. F..sup.+ bottoms fraction is recycled to the first hydroisomerization zone.
- 13. A process for producing middle distillate fuel products from a Fischer-Tropsch wax containing oxygenate compounds, which process comprises:
- (1) separating the Fischer-Tropsch wax into (a) a low-boiling fraction which contains most of the oxygenate compounds and (b) a high-boiling fraction which is substantially free of water and oxygenate compounds;
- (2) reacting the high-boiling fraction from step (1) with hydrogen in a hydroisomerization zone in the presence of a fluorided Group VIII metal-on-alumina catalyst to convert from about 50 to about 95 percent of the 700.degree. F.+ material present in the high-boiling fraction thereby maximizing the production of middle distillate product boiling in the range about 320.degree. F. to 700.degree. F., said catalyst having (a) a bulk fluoride concentration ranging from about 2 to about 10 weight percent, wherein the fluoride concentration is less than about 3.0 weight percent at the outer surface layer to a depth less than one one hundredth of an inch, provided the surface fluoride concentration is less than the bulk fluoride concentration, (b) an aluminum fluoride hydroxide hydrate level greater than about 60 where an aluminum fluoride hydroxide hydrate level of 100 corresponds to the X-ray diffraction peak height at 5.66 .ANG. for a Reference Standard and (c) a N/Al ratio less than about 0.005; and
- (3) separating the product from step (2) into at least one fraction having a final boiling point below about 320.degree. F. at atmospheric pressure, a middle distillate fraction boiling in the range of about 320.degree.-700.degree. F. at atmospheric pressure and a residual fraction having an initial boiling point above 700.degree. F. at atmospheric pressure.
- 14. The process of claim 13 wherein said Group VIII metal is platinum.
- 15. The process of claim 14 wherein the catalyst employed in step (2) has an aluminum fluoride hydrate level of at least 80.
- 16. The process of claim 15 wherein said catalyst contains about 0.1 to 2 weight percent platinum and about 5 to 8 percent fluoride.
- 17. The process of claim 16 wherein the catalyst has a N/Al ratio less than about 0.002 and a fluoride concentration on the outer surface less than about 1.0 weight percent.
- 18. The process of claim 17 wherein the Fischer-Tropsch wax is separated in step (1) to produce a high-boiling fraction having an initial boiling point between about 450.degree. F. and about 650.degree. F. at atmospheric pressure.
- 19. The process of claim 18 wherein the unconverted 700.degree. F..sup.+ fraction in the product is recovered and recycled to the hydroisomerization zone.
- 20. The process of claim 19 wherein the catalyst employed in step (2) has an aluminum fluoride hydrate level of at least about 100 and a fluoride concentration on the outer surface of less than about 0.5 weight percent.
- 21. The process of claim 20 wherein from about 70 wt % to about 90 wt % of the 700.degree. F..sup.+ material present in the feed to the hydroisomerization zone is converted therein.
- 22. The process of claim 21 wherein the Fischer-Tropsch wax is separated in step (1) to produce a high-boiling fraction having an initial boiling point between about 500.degree. F. and about 650.degree. F. at atmospheric pressure.
- 23. The process of claim 22 wherein the low-boiling fraction from step (1) is combined with the 320.degree. F.-700.degree. F. fraction from step (3).
- 24. The process of claim 23 wherein wherein at least a portion of the residual fraction from step (3) is sent to a second hydroisomerization zone containing the catalyst described for use in the first hydroisomerization for contact with hydrogen and wherein the effluent from the second isomerization zone is fractionated into a light ends fraction boiling below about 700.degree. F., a lubricating oil fraction boiling in the range of about 650.degree. F. to 950.degree. F. and a bottoms fraction having an initial boiling point above about 950.degree. F.
- 25. The process of claim 24 wherein the 950.degree. F..sup.+ bottoms fraction is recycled to the first hydroisomerization zone.
- 26. The process of claim 25 comprising recovering a low pour point lubricating oil fraction in the absence of any dewaxing process step.
CROSS REFERENCE TO PRIOR APPLICATION
This is a Continuation-in-Part application of prior application Ser. No. 134,960 filed December 18, 1987, now abandoned, which is the subject of a petition to revive an unintentionally abandoned application.
US Referenced Citations (12)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
134960 |
Dec 1987 |
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