Patent US3862028A successfully refreshed from Google Patents.
US3862028A
Expired / Lapsed
US
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Flotation-beneficiation of phosphate ores
Assignee: United States Department of Agriculture
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Filing: 1973-11-20
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Granted: 1975-01-21
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Expires: 1993-11-20
Abstract
Abstract An improved method of separating minerals from phosphate ores is described. The addition of silica depressants to flotation slurries substantially increases the efficiency of mineral separation and thereby reduces the number of flotation steps required to obtain a good yield of ore having the desired mineral concentration.
Inventors
- 👤 Duane A Jones
- 👤 Wesley A Jordan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:59
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
33 words
The method described in claim 1 in which the graft polymer contains from about 2.5 to 15 percent by weight of a polymerized quaternary ammonium derivative of aminotrialkyl methacrylate consisting of 2-hydroxy-3-methacryloyloxypropyltrimethylammonium chloride.
Claim 2
Dependent Claim
43 words
The method described in claim 1 in which the graft polymer contains from about 2 to 11 percent by weight of a polymerized quaternary ammonium derivative of aminotrialkyl methacrylate consisting of 2-hydroxy-3-methacryloyloxypropyltrimethylammonium chloride and from about 5 to 20 percent by weight polyacrylamide.
Claim 3
Dependent Claim
25 words
The method described in claim 2 in which the ore is floated in the presence of 0.05 pound/ton of ore of the starch graft polymer.
Claim 4
Dependent Claim
25 words
The method described in claim 3 in which the ore is floated in the presence of 0.05 pound/ton of ore of the starch graft polymer.
References Cited (Backward Citations)
US2740522A
Cited
US3138550A
Cited
US3321649A
Cited
US3575868A
Cited
US3635857A
Cited
US3669915A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |