US4398978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High density, low viscosity airbreather fuel (RJ-4-I)
Assignee: United States Department of the Navy
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Filing: 1982-04-26
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Granted: 1983-08-16
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Expires: 2002-04-26
Abstract
Abstract A method for preparation of high density, high energy, low viscosity liquid hydrocarbon fuel by catalytic treatment of tetrahydrodimethyldicyclopentadiene (RJ-4) synthetic fuel. Endo-isomers within the fuel stock are isomerized to exo-isomers by treatment of the fuel stock with catalysts such as aluminum chloride, nickel, or pulverized, acid treated firebrick resulting in a fuel having a lower viscosity than the original RJ-4.
Inventors
- 👤 George W. Burdette
- 👤 Abraham I. Schneider
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:03
CPC Classifications
C; C10; C10L; C10L1/00; C10L1/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
55 words
A process for making a high density, low viscosity liquid airbreather fuel, isomerized RJ-4, comprising the steps of: (a) contacting RJ-4, comprising both endo-tetrahydrodimethylidicylopentadiene and exo-tetrahydrodimethyldicyclopentadiene isomers, with a catalyst consisting essentially of an AlCl 3 -olefin complex; and (b) treating for a sufficient time to obtain isomerized RJ-4 consisting essentially of the exo-tetrahydrodimethyldicyclopentadiene isomer.
Claim 2
Dependent Claim
55 words
A process for making a high density, low viscosity liquid airbreather fuel, isomerized RJ-4, comprising the steps of: (a) contacting RJ-4, comprising both endo-tetrahydrodimethylidicylopentadiene and exo-tetrahydrodimethyldicyclopentadiene isomers, with a catalyst consisting essentially of an AlCl 3 -olefin complex; and (b) treating for a sufficient time to obtain isomerized RJ-4 consisting essentially of the exo-tetrahydrodimethyldicyclopentadiene isomer.
Claim 3
Dependent Claim
35 words
The process of claim 1 wherein the mole ratio of AlCl 3 -olefin complex to RJ-4 is in the range of about 0.002 to 1 to about 0.5 to 1 based upon AlCl 3 .
Claim 4
Dependent Claim
30 words
The process of claim 1 wherein the mole ratio of AlCl 3 -olefin complex to RJ-4 is in the range of about 0.01 to 1 to about 0.02 to 1.
Claim 5
Dependent Claim
25 words
The process of claim 1 wherein said treatment step is carried out at temperatures within the range of about 0° C. and about 200° C.
Claim 6
Dependent Claim
25 words
The process of claim 1 wherein said treatment step is carried out at temperatures within the range of about 85° C. and about 95° C.
Claim 7
Dependent Claim
25 words
The process of claim 1 wherein treatment is carried out for a time period within the range of about 30 minutes to about 15 hours.
Claim 8
Dependent Claim
40 words
The process of claim 1 wherein treatment is carried out for a time period which is terminated upon measurement of a predetermined reactant viscosity below that of the RJ-4 feed, said measured viscosity being that of the desired isomerized RJ-4.
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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) | 1986-08-15 | 1987-02-14 | 1987-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-15 | 1991-02-14 | 1991-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-15 | 1995-02-14 | 1995-08-16 | $7700.00 | Window Closed / Lapsed |