US3380819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing arsenic from iron ores
Assignee: Premium Iron Ores Ltd
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Filing: 1966-01-28
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Granted: 1968-04-30
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Expires: 1986-01-28
Abstract
No abstract record available.
Inventors
- 👤 Cavanagh Patrick Edgar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:57
CPC Classifications
C; C22; C22B; C22B1/00; C22B1/14; C22B1/02; C22B1/11
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
59 words
A LOW TEMPERATURE METHOD FOR REMOVING MOST OF THE ARSENIC FROM ORES CONTAINING ARSENIC AND MINERALS NORMALLY FORMING ARSENATES THEREWITH ON HEATING TO ROASTING TEMPERATURES AND COMPRISING: HEATING SAID ORE IN AN ATMOSPHERE CONTAINING BETWEEN ABOUT 1% AND ABOUT 6% OXYGEN AND AT A TEMPERATURE BETWEEN ABOUT 1500*F. AND ABOUT 1700*F. FOR ABOUT ONE HOUR TO FORM GASEOUS ARSENIC.
Claim 2
Dependent Claim
59 words
A LOW TEMPERATURE METHOD FOR REMOVING MOST OF THE ARSENIC FROM ORES CONTAINING ARSENIC AND MINERALS NORMALLY FORMING ARSENATES THEREWITH ON HEATING TO ROASTING TEMPERATURES AND COMPRISING: HEATING SAID ORE IN AN ATMOSPHERE CONTAINING BETWEEN ABOUT 1% AND ABOUT 6% OXYGEN AND AT A TEMPERATURE BETWEEN ABOUT 1500*F. AND ABOUT 1700*F. FOR ABOUT ONE HOUR TO FORM GASEOUS ARSENIC.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-04-30 | 1971-10-30 | 1972-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-04-30 | 1975-10-30 | 1976-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-04-30 | 1979-10-30 | 1980-04-30 | $7700.00 | Window Closed / Lapsed |