US2624744A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of maleic anhydride
Assignee: Monsanto Chemicals Ltd
•
Filing: 1949-11-10
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Granted: 1953-01-06
•
Expires: 1969-11-10
Abstract
No abstract record available.
Inventors
- 👤 Joseph R Darby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:30
CPC Classifications
C; C07; C07C; C07C57/00; C07C57/02; C07C57/13; C07C57/145; C07C51/00; C07C51/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
IN THE PROCESS OF TRANSFERRING A GASEOUS MIXTURE COMPRISING GASEOUS MALEIC ANHYDRIDE AND OXYGEN AT AN ELEVATED TEMPERATURE THROUGH AN APPARATUS HAVING AN IRON AS A BASIC COMPONENT, THE STEP WHICH COMPRISES PASSING SAID MIXTURE WHILE AT AN ELEVATED TEMPERATURE ABOVE 300* C. IN CONTACT WITH A SURFACE OF THE APPARATUS WHICH HAS BEEN EXPOSED TO AN ATMOSPHERE COMPRISING AMMONIA AT AN ELEVATED TEMPERATURE OF AT LEAST 300* C.
Claim 2
Dependent Claim
69 words
IN THE PROCESS OF TRANSFERRING A GASEOUS MIXTURE COMPRISING GASEOUS MALEIC ANHYDRIDE AND OXYGEN AT AN ELEVATED TEMPERATURE THROUGH AN APPARATUS HAVING AN IRON AS A BASIC COMPONENT, THE STEP WHICH COMPRISES PASSING SAID MIXTURE WHILE AT AN ELEVATED TEMPERATURE ABOVE 300* C. IN CONTACT WITH A SURFACE OF THE APPARATUS WHICH HAS BEEN EXPOSED TO AN ATMOSPHERE COMPRISING AMMONIA AT AN ELEVATED TEMPERATURE OF AT LEAST 300* C.
References Cited (Backward Citations)
US1941271A
Cited
US2099350A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-01-06 | 1956-07-07 | 1957-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-01-06 | 1960-07-07 | 1961-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-01-06 | 1964-07-07 | 1965-01-06 | $7700.00 | Window Closed / Lapsed |