Patent US3000908A successfully refreshed from Google Patents.
US3000908A
Expired / Lapsed
US
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Catalysis of the vapor phase partial ox-
Assignee: —
•
Filing: —
•
Granted: 1961-09-19
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Expires: 1978-09-19
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:08
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/002; B01J21/00; B01J21/06; B01J21/063; B01J23/16; B01J23/20; B01J23/22; C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/255; C07C51/265; C07C63/00; C07C63/14; C07C63/15; C07C63/16; C07D; C07D307/00; C07D307/77; C07D307/87; C07D307/89
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
108 words
A PROCESS FOR THE VAPOR PHASE CATALYTIC OXIDATION OF NAPHTHALENE TO PHTHALIC ANHYDRIDE WHICH COMPRISES PASSING AIR CONTAINING FROM ABOUT 0.75 TO ABOUT 2.25 MOLE PERCENT NAPHTHALENE VAPORS INTO CONTACT WITH A CATALYST MAINTAINED IN THE APPROXIMATE TEMPERATURE RANGE 320* C. TO 420*C., SAID CATALYST BEING A SOLUTION, DISTRIBUTED ON SILICA GEL, OF VANADIUM PENTOXIDE IN A MIXTURE OF ALKALI METAL SALTS OF PYROSULFURIC ACID, THE ALKALI METAL PORTION OF SAID MIXTURE OF SALTS COMPRISING FROM ABOUT 35 TO ABOUT 90 MOLE PERCENT POTASSIUM AND FROM ABOUT 35 TO ABOUT 10 MOLE PERCENT OF AT LEAST ONE ALKALI METAL SELECTED FROM THE GROUP CONSISTING OF RUBIDIUM AND CESIUM.
Claim 2
Dependent Claim
108 words
A PROCESS FOR THE VAPOR PHASE CATALYTIC OXIDATION OF NAPHTHALENE TO PHTHALIC ANHYDRIDE WHICH COMPRISES PASSING AIR CONTAINING FROM ABOUT 0.75 TO ABOUT 2.25 MOLE PERCENT NAPHTHALENE VAPORS INTO CONTACT WITH A CATALYST MAINTAINED IN THE APPROXIMATE TEMPERATURE RANGE 320* C. TO 420*C., SAID CATALYST BEING A SOLUTION, DISTRIBUTED ON SILICA GEL, OF VANADIUM PENTOXIDE IN A MIXTURE OF ALKALI METAL SALTS OF PYROSULFURIC ACID, THE ALKALI METAL PORTION OF SAID MIXTURE OF SALTS COMPRISING FROM ABOUT 35 TO ABOUT 90 MOLE PERCENT POTASSIUM AND FROM ABOUT 35 TO ABOUT 10 MOLE PERCENT OF AT LEAST ONE ALKALI METAL SELECTED FROM THE GROUP CONSISTING OF RUBIDIUM AND CESIUM.
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) | 1964-09-18 | 1965-03-20 | 1965-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-09-18 | 1969-03-20 | 1969-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-09-18 | 1973-03-20 | 1973-09-19 | $7700.00 | Window Closed / Lapsed |