US2518312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of maleic or phthalic anhydride from wet process gas mixtures
Assignee: EIDP Inc
•
Filing: 1947-06-16
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Granted: 1950-08-08
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Expires: 1967-06-16
Abstract
No abstract record available.
Inventors
- 👤 Hartig Martval John Paul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:29
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/47
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
71 words
THE METHOD OF RECOVERING AN ANHYDRIDE FROM THE GROUP CONSISTING OF MALEIC AND PHTHALIC ANHYDRIDE, FROM A WET PROCESS GAS MIXTURE CONTAINING SAID ANHYDRIDE, WHICH PROCESS COMPRISES ABSORBING SAID ANHYDRIDE ON AN ABSORBENT FROM THE GROUP CONSSITING OF ACTIVATED CARBON AND SILICA GEL, AT A TEMPERATURE ABOVE THAT AT WHICH SAID ABSORBENT ABSORBS A MAXIMUM OF 2% BY WEIGHT OF WATER AND BELOW 130*C., AND REMOVING SAID ANHYDRIDE FROM SAID ABSORBENT.
Claim 2
Independent Claim
71 words
THE METHOD OF RECOVERING AN ANHYDRIDE FROM THE GROUP CONSISTING OF MALEIC AND PHTHALIC ANHYDRIDE, FROM A WET PROCESS GAS MIXTURE CONTAINING SAID ANHYDRIDE, WHICH PROCESS COMPRISES ABSORBING SAID ANHYDRIDE ON AN ABSORBENT FROM THE GROUP CONSSITING OF ACTIVATED CARBON AND SILICA GEL, AT A TEMPERATURE ABOVE THAT AT WHICH SAID ABSORBENT ABSORBS A MAXIMUM OF 2% BY WEIGHT OF WATER AND BELOW 130*C., AND REMOVING SAID ANHYDRIDE FROM SAID ABSORBENT.
References Cited (Backward Citations)
US1742247A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-07 | 1954-02-06 | 1954-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-07 | 1958-02-06 | 1958-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-07 | 1962-02-06 | 1962-08-08 | $7700.00 | Window Closed / Lapsed |