Patent US2670355A successfully refreshed from Google Patents.
US2670355A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of maleic anhydride
Assignee: BARSKY
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Filing: 1950-02-23
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Granted: 1954-02-23
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Expires: 1970-02-23
Abstract
No abstract record available.
Inventors
- 👤 Barsky George
- 👤 Gottfried Sidney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:58
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/54; C07C51/56
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
148 words
THE METHOD OF RECOVERING MALEIC ANHYDRIDE FROM A MIXTURE OF MALEIC ANHYDRIDE VAPOR AND WATER VAPOR CONTAINING AT LEAST ABOUT FIVE MOLECULAR PERCENT OF MALEIC ANHYDRIDE, THE COMPOSITION OF SAID MIXTURE BEING SUCH THAT IT WOULD CONDENSE AT A TEMPERATURE NOT ABOVE THE TRIPLE POINT, WHICH CONSISTS IN ADDING THERETO MALEIC ANHYDRIDE IN SUFFICIENT AMOUNT TO PROVIDE A MIXTURE WHICH WOULD CONDENSE AT A TEMPERATURE ABOVE THE TRIPLE POINT, FRACTIONALLY CONDENSING AT A PRESSURE NOT IN EXCESS OF ATMOSPHERIC SAID MIXTURE OF VAPORS AT A TEMPERATURE ABOVE THAT OF THE TRIPLE POINT AT WHICH A VAPOR PHASE COMPRISING MALEIC ANHYDRIDE AND WATER, A LIQUID PHASE COMPRISING MALEIC ANHYDRIDE AND MALEIC ACID, AND A SOLID PHASE COMPRISING MALEIC ANHYDRIDE AND MALEIC ACID CAN CO-EXIST IN EQUILIBRIUM AT THE PRESSURE AT WHICH CONDENSATION OCCURS, AND THEREAFTER FRACTIONALLY DISTILLING THE CONDENSATE AND SEPARATING THE MALEIC ANHYDRIDE AS THE HIGH BOILING FRACTION.
Claim 2
Independent Claim
148 words
THE METHOD OF RECOVERING MALEIC ANHYDRIDE FROM A MIXTURE OF MALEIC ANHYDRIDE VAPOR AND WATER VAPOR CONTAINING AT LEAST ABOUT FIVE MOLECULAR PERCENT OF MALEIC ANHYDRIDE, THE COMPOSITION OF SAID MIXTURE BEING SUCH THAT IT WOULD CONDENSE AT A TEMPERATURE NOT ABOVE THE TRIPLE POINT, WHICH CONSISTS IN ADDING THERETO MALEIC ANHYDRIDE IN SUFFICIENT AMOUNT TO PROVIDE A MIXTURE WHICH WOULD CONDENSE AT A TEMPERATURE ABOVE THE TRIPLE POINT, FRACTIONALLY CONDENSING AT A PRESSURE NOT IN EXCESS OF ATMOSPHERIC SAID MIXTURE OF VAPORS AT A TEMPERATURE ABOVE THAT OF THE TRIPLE POINT AT WHICH A VAPOR PHASE COMPRISING MALEIC ANHYDRIDE AND WATER, A LIQUID PHASE COMPRISING MALEIC ANHYDRIDE AND MALEIC ACID, AND A SOLID PHASE COMPRISING MALEIC ANHYDRIDE AND MALEIC ACID CAN CO-EXIST IN EQUILIBRIUM AT THE PRESSURE AT WHICH CONDENSATION OCCURS, AND THEREAFTER FRACTIONALLY DISTILLING THE CONDENSATE AND SEPARATING THE MALEIC ANHYDRIDE AS THE HIGH BOILING FRACTION.
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) | 1957-02-22 | 1957-08-24 | 1958-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-22 | 1961-08-24 | 1962-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-22 | 1965-08-24 | 1966-02-23 | $7700.00 | Window Closed / Lapsed |