Patent US2942940A successfully refreshed from Google Patents.
US2942940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for extracting tungsten values
Assignee: General Electric Co
•
Filing: 1956-05-22
•
Granted: 1960-06-28
•
Expires: 1976-05-22
Abstract
No abstract record available.
Inventors
- 👤 Robert C Osthoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:16
CPC Classifications
C; C01; C01G; C01G41/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
59 words
A PROCESS OF EXTRACTING TUNGSTEN VALUES FROM A TUNGSTEN COMPOSITION WHICH PROCESS COMPRISES: (1) TREATING AN AQUEOUS MIXTURE OF SAID TUNGSTEN COMPOSITION AND OXALIC ACID WITH AMMONIA AND THEREAFTER REACTING THE TUNGSTEN COMPOSITION WITH THE REACTION PRODUCT OF OXALIC ACID AND AMMONIA, (2) SEPARATING THE AMMONUIM PARATUNGSTATE SOLUTION SO FORMED, AND (3) DECOMPOSING THE AMMONUIM PARATUNGSTATE TO TUNGSTIC ACID.
References Cited (Backward Citations)
US2600655A
Cited
US2802718A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-28 | 1963-12-28 | 1964-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-28 | 1967-12-28 | 1968-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-28 | 1971-12-28 | 1972-06-28 | $7700.00 | Window Closed / Lapsed |