US3645455A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of lubricant-grade molybdenite from byproduct concentrates of porphyry copper ores
Assignee: Kennecott Corp
•
Filing: 1969-04-04
•
Granted: 1972-02-29
•
Expires: 1989-04-04
Abstract
Abstract Lubricant-grade molybdenite is produced from byproduct molybdenite flotation concentrates of porphyry copper ores by a sequence of purification steps which include controlled grinding to liberate contaminant minerals and to flatten the molybdenite, followed by a flotation step for the selective recovery of the so-flattened molybdenite. The grinding is controlled to soften impact and minimize duration of the grinding period.
Inventors
- 👤 Cecilio O Castillo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:50
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
24 words
A process in accordance with claim 1, wherein the molybdenite concentrate feed to the process is preliminarily treated for quantity reduction of gangue impurities.
Claim 2
Dependent Claim
30 words
A process in accordance with claim 2, wherein the preliminary treatment comprises sizing the molybdenite concentrate feed, and passing only the fines fraction resulting therefrom to the impact grinding step.
Claim 3
Dependent Claim
32 words
A process in accordance with claim 3, wherein before passing the fines fraction to the impact grinding step, said fraction is treated for removal of carryover collector reagents from mineral particle surfaces.
Claim 4
Dependent Claim
34 words
A process in accordance with claim 4, wherein the coarse fraction is subjected to grinding and conditioning in preparation for flotation and is then subjected to flotation for the recovery of molybdenite contained thereby.
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) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |