US3187016A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of phthalic anhydride
Assignee: Halcon Research and Development Corp
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Filing: 1961-10-16
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Granted: 1965-06-01
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Expires: 1981-10-16
Abstract
No abstract record available.
Inventors
- 👤 Brown David
- 👤 Alfred V Cowan
- 👤 John H Lutz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:53
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/54; C07C51/573
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
IN A PROCESS FOR THE PRODUCTION OF PHTHALIC ANHYDRIDE WHEREIN A SUITABLE HYDROCARBON IS PARTIALLY OXIDIZED IN THE VAPOR PHASE TO FORM A REACTOR EFFLUENT CONTAINING PHTHALIC ANHYDRIDE, THE IMPROVEMENT OF PASSING SAID REACTOR EFFLUENT INTO A QUENCHING ZONE; CONTACTING SAID EFFLUENT WITH METHYLNAPHTHALENE THEREBY COOLING SAID EFFLUENT AND FORMING A SLURRY CONTAINING SOLID PHTHALIC ANHYDRIDE; SEPARATING THE CRUDE PHTHALIC ANHYDRIDE FROM SAID SLURRY; AND DISTILLING THE CRUDE PHTHALIC ANHYDRIDE AND SEPARATING PURE PHTHALIC ANHYDRIDE AS A DISTILLATE.
Claim 2
Dependent Claim
78 words
IN A PROCESS FOR THE PRODUCTION OF PHTHALIC ANHYDRIDE WHEREIN A SUITABLE HYDROCARBON IS PARTIALLY OXIDIZED IN THE VAPOR PHASE TO FORM A REACTOR EFFLUENT CONTAINING PHTHALIC ANHYDRIDE, THE IMPROVEMENT OF PASSING SAID REACTOR EFFLUENT INTO A QUENCHING ZONE; CONTACTING SAID EFFLUENT WITH METHYLNAPHTHALENE THEREBY COOLING SAID EFFLUENT AND FORMING A SLURRY CONTAINING SOLID PHTHALIC ANHYDRIDE; SEPARATING THE CRUDE PHTHALIC ANHYDRIDE FROM SAID SLURRY; AND DISTILLING THE CRUDE PHTHALIC ANHYDRIDE AND SEPARATING PURE PHTHALIC ANHYDRIDE AS A DISTILLATE.
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) | 1968-05-31 | 1968-11-30 | 1969-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-05-31 | 1972-11-30 | 1973-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-05-31 | 1976-11-30 | 1977-06-01 | $7700.00 | Window Closed / Lapsed |