Patent US4428819A successfully refreshed from Google Patents.
US4428819A
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Hydroisomerization of catalytically dewaxed lubricating oils
Assignee: Mobil Oil AS
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Filing: 1982-07-22
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Granted: 1984-01-31
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Expires: 2002-07-22
Abstract
Abstract The quality of catalytically hydrodewaxed oils is improved by hydroisomerizing the oil to remove residual waxy components which contribute to poor performance in the Overnight Cloud Point test. Conversion during the hydroisomerization is minimized so as to obtain a product of high clarity in good yield.
Inventors
- 👤 Paul Shu
- 👤 Tsoung-Yuan Yan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:54
CPC Classifications
C; C10; C10G; C10G45/00; C10G45/58; C10G45/60; C10G45/64; C10G2400/00; C10G2400/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
79 words
A process for improving the overnight cloud point of a catalytically dewaxed lubricating oil stock containing petrolatum wax which is relatively insoluble comprising contacting said oil with a catalyst having both an acidic function and a hydrogenation-dehydrogenation function in the presence of hydrogen at hydroisomerization conditions to produce a product containing branched chain isoparaffins which are more soluble at low temperatures, and wherein the conversion of said oil to lower boiling components is less than about 10 weight percent.
Claim 2
Dependent Claim
79 words
A process for improving the overnight cloud point of a catalytically dewaxed lubricating oil stock containing petrolatum wax which is relatively insoluble comprising contacting said oil with a catalyst having both an acidic function and a hydrogenation-dehydrogenation function in the presence of hydrogen at hydroisomerization conditions to produce a product containing branched chain isoparaffins which are more soluble at low temperatures, and wherein the conversion of said oil to lower boiling components is less than about 10 weight percent.
Claim 3
Dependent Claim
24 words
A method according to claim 1 in which the hydrogenation component comprises a metal component of Group VIA or VIIIA of the Periodic Table.
Claim 4
Dependent Claim
15 words
A method according to claim 1 in which the acidic component comprises a crystalline zeolite.
Claim 5
Dependent Claim
24 words
A method according to claim 1 in which the acidic component comprises a large pore zeolite having a Constraint Index of less than 1.
Claim 6
Dependent Claim
30 words
A method according to claim 1 in which the acidic component comprises a zeolite having a silica:alumina ratio of at least 12:1 and a Constraint Index of 1 to 12.
Claim 7
Dependent Claim
37 words
A method according to claim 1 in which the hydrodewaxed oil is hydroisomerized at a temperature of 200° C. to 450° C., a pressure of 400 to 25000 kPa and a space velocity of 0.1 to 10.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-30 | 1987-08-01 | 1988-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-30 | 1991-08-01 | 1992-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-30 | 1995-08-01 | 1996-01-31 | $7700.00 | Window Closed / Lapsed |