Patent US4288644A successfully refreshed from Google Patents.
US4288644A
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Process for isomerization of tetrahydrodimethyldicyclopentadiene
Assignee: Sunoco Inc R&M
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Filing: 1979-12-19
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Granted: 1981-09-08
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Expires: 1999-12-19
Abstract
Abstract Tetrahydrodimethyldicyclopentadiene is catalytically isomerized to a liquid isomeric mixture having a suitable low temperature viscosity making it suitable as a missile fuel. The catalyst comprises an acidic alumina. Hydrogen is also present and in an amount sufficient to maintain the isomerization activity of the alumina. The elevated temperature is sufficient to cause isomerization.
Inventors
- 👤 Edward J. Janoski
- 👤 Abraham Schneider
- 👤 Richard E. Ware
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:19
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/22; C07C5/2206; C07C5/226; C07C2521/00; C07C2521/14; C07C2521/16; C07C2521/18; C07C2523/00; C07C2523/38; C07C2523/40; C07C2523/44; C07C2523/70; C07C2523/74; C07C2523/755; C07C2523/89; C07C2603/00; C07C2603/56; C07C2603/58; C07C2603/60; C07C2603/66; C07C2603/68
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
74 words
Process for the catalytic isomerization of endo tetrahydrodimethyldicyclopentadiene comprising: (a) contacting endo tetrahydrodimethyldicyclopentadiene with a catalytic amount of acidic alumina having isomeric activity; (b) having the contacting occur at an isomerization temperature in the range of from about 100° C. to about 400° C. and in the presence of sufficient hydrogen to maintain the isomeric activity of the alumina; and (c) continuing the contacting until the endo diene is isomerized to its exo isomer.
Claim 2
Dependent Claim
74 words
Process for the catalytic isomerization of endo tetrahydrodimethyldicyclopentadiene comprising: (a) contacting endo tetrahydrodimethyldicyclopentadiene with a catalytic amount of acidic alumina having isomeric activity; (b) having the contacting occur at an isomerization temperature in the range of from about 100° C. to about 400° C. and in the presence of sufficient hydrogen to maintain the isomeric activity of the alumina; and (c) continuing the contacting until the endo diene is isomerized to its exo isomer.
Claim 3
Dependent Claim
17 words
Process according to claim 1 wherein in addition to the acidic alumina a hydrogenation metal is present.
Claim 4
Dependent Claim
13 words
Process according to claim 1 or 2 wherein the acidic alumina is silica-alumina.
Claim 5
Dependent Claim
13 words
Process according to claim 2 wherein the hydrogenation metal is palladium or nickel.
Claim 6
Dependent Claim
49 words
Process according to claim 2 wherein the catalyst is (1) a mixture of palladium on carbon and an acid clay; (2) a mixture of palladium on carbon and nickel on silica alumina; or (3) palladium on alumina, and the hydrogen has a pressure of at least about 30 psig.
Claim 7
Dependent Claim
32 words
Process according to claim 2 wherein the catalyst is a mixture of palladium on carbon and nickel on silica alumina and the hydrogen has a pressure of at least about 105 psig.
Claim 8
Dependent Claim
24 words
Process according to claim 2 wherein the catalyst is nickel on silica-alumina and the hydrogen has a pressure of at least about 200 psig.
Claim 9
Dependent Claim
35 words
Process according to claim 1 wherein the catalyst to the diene ratio ranges between from about one-half part by weight of catalyst per hundred parts by weight of the diene to about one to one.
Claim 10
Dependent Claim
28 words
Process according to claim 5, 6 or 7 wherein the resulting isomer mixture has a density (20° C.)/4 in the range between from about 0.911 to about 0.918.
Claim 11
Dependent Claim
32 words
Process according to claim 5, 6 or 8 wherein the resulting isomer mixture has a kinematic viscosity @ 100° F. in the range between from about 2 cst to about 3 cst.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-09-07 | 1985-03-09 | 1985-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-07 | 1989-03-09 | 1989-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-07 | 1993-03-09 | 1993-09-08 | $7700.00 | Window Closed / Lapsed |