US2788367A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Xylene oxidation process
Assignee: Union Oil Company of California
•
Filing: 1953-03-05
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Granted: 1957-04-09
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Expires: 1973-03-05
Abstract
No abstract record available.
Inventors
- 👤 John L Bills
- 👤 William L Stanley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:08
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/255; C07C51/265
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
A PROCESS FOR OXIDIZING XYLENE TO PRODUCE PHTHALIC ACID WHICH COMPRISES CONTACTING XYLENE IN THE LIQUID PHASE, IN THE PRESENCE OF AN OXIDATION CATALYST, WITH A GAS CONTAINING FREE OXYGEN AT A TEMPERATURE BETWEEN ABOUT 100* C. AND ABOUT 160* C., SEPARATING PHTHALIC ACID FROM THE REACTION MIXTURE, DISTILLING ABOUT 15 TO 50% OF THE LIQUID PORTION OF THE REACTION MIXTURE TO A TEMPERATURE SUFFICIENT TO VAPORIZE TOLUIC ACIDS, DISCARDING THE DISTILLATION RESIDUE, AND RETURNING ANY UNDISTILLED LIQUID REACTION MIXTURE AND THE RESULTING DISTILLATE FOR FURTHER OXIDATION.
Claim 2
Dependent Claim
87 words
A PROCESS FOR OXIDIZING XYLENE TO PRODUCE PHTHALIC ACID WHICH COMPRISES CONTACTING XYLENE IN THE LIQUID PHASE, IN THE PRESENCE OF AN OXIDATION CATALYST, WITH A GAS CONTAINING FREE OXYGEN AT A TEMPERATURE BETWEEN ABOUT 100* C. AND ABOUT 160* C., SEPARATING PHTHALIC ACID FROM THE REACTION MIXTURE, DISTILLING ABOUT 15 TO 50% OF THE LIQUID PORTION OF THE REACTION MIXTURE TO A TEMPERATURE SUFFICIENT TO VAPORIZE TOLUIC ACIDS, DISCARDING THE DISTILLATION RESIDUE, AND RETURNING ANY UNDISTILLED LIQUID REACTION MIXTURE AND THE RESULTING DISTILLATE FOR FURTHER OXIDATION.
References Cited (Backward Citations)
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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) | 1960-04-08 | 1960-10-08 | 1961-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-04-08 | 1964-10-08 | 1965-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-04-08 | 1968-10-08 | 1969-04-09 | $7700.00 | Window Closed / Lapsed |