Patent US691569A successfully refreshed from Google Patents.
Patent US3319785A successfully refreshed from Google Patents.
US3319785A
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Flotation process for the purification of silicon carbide
Assignee: Elektroschmelzwerk Kempten GmbH
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Filing: 1964-08-24
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Granted: 1967-05-16
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Expires: 1984-08-24
Abstract
No abstract record available.
Inventors
- 👤 Schroll Franz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:17
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/001; B03D1/004; B03D1/01; B03D1/011; C; C01; C01B; C01B32/00; C01B32/90; C01B32/914; C01B32/956; C01B32/963; C01B32/97; B03D2203/00; B03D2203/02; B03D2203/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
84 words
IN A PROCESS FOR THE SEPARATION OF CRYSTALLINE SILICON CARBIDE FROM SUBSTANTIALLY CARBON-FREE CRUDE SILICON CARBIDE PRODUCED FROM COAL AND SAND, THE STEP WHICH CONSISTS OF SUBJECTING SAID SUBSTANTIALLY CARBON-FREE SILICON CARBIDE IN PARTICLE SIZE NOT SUBSTANTIALLY IN EXCESS OF 1.5 MM. TO FLOTATION IN AN AQUEOUS MEDIUM IN THE PRESENCE OF A CATION-ACTIVE FLOTATION AGENT SELECTED FROM THE GROUP CONSISTING OF PRIMARY, SECONDARY AND TERTIARY ALKYL AMINE SALTS AND QUATERNARY AMMONIUM SALTS, AND RECOVERING THE RESULTANT FOAM WITH THE ADHERING CRYSTALLINE SILICON CARBIDE.
Claim 2
Dependent Claim
84 words
IN A PROCESS FOR THE SEPARATION OF CRYSTALLINE SILICON CARBIDE FROM SUBSTANTIALLY CARBON-FREE CRUDE SILICON CARBIDE PRODUCED FROM COAL AND SAND, THE STEP WHICH CONSISTS OF SUBJECTING SAID SUBSTANTIALLY CARBON-FREE SILICON CARBIDE IN PARTICLE SIZE NOT SUBSTANTIALLY IN EXCESS OF 1.5 MM. TO FLOTATION IN AN AQUEOUS MEDIUM IN THE PRESENCE OF A CATION-ACTIVE FLOTATION AGENT SELECTED FROM THE GROUP CONSISTING OF PRIMARY, SECONDARY AND TERTIARY ALKYL AMINE SALTS AND QUATERNARY AMMONIUM SALTS, AND RECOVERING THE RESULTANT FOAM WITH THE ADHERING CRYSTALLINE SILICON CARBIDE.
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) | 1970-05-15 | 1970-11-14 | 1971-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-05-15 | 1974-11-14 | 1975-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-05-15 | 1978-11-14 | 1979-05-16 | $7700.00 | Window Closed / Lapsed |