Patent US2839361A successfully refreshed from Google Patents.
US2839361A
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Defluorination of phosphate rock
Assignee: SMITH DOUGLASS CO Inc
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Filing: 1954-10-14
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Granted: 1958-06-17
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Expires: 1974-10-14
Abstract
No abstract record available.
Inventors
- 👤 Clinton A Hollingsworth
- 👤 John C Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:54
CPC Classifications
C; C05; C05B; C05B13/00; C05B13/02; Y; Y10; Y10S; Y10S71/00; Y10S71/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
THE METHOD OF DEFLUORINATING PHOSPHATE ROCK WHICH COMPRISES SUBJECTING THE ROCK WITH A SILICA CONTENT OF FROM 2 TO 6% TO CALCINATION AT A TEMPERATURE OF AT LEAST 2600*F. WITHOUT SUBSTANTIAL FUSION IN THE PRESENCE OF WATER VAPOR AND OF A REAGENT MIXTURE CONSISTING ESSENTIALLY OF SODIUM CHLORIDE AND PHOSPHORIC ACID, THE MOLRATIO OF THE SODIUM AND PHOSPHORUS CONTENTS (CALCULATED AS NA2O AND P2O5 RESPECTIVELY) OF THE REAGENT MIXTURE BEING BETWEEN 1.6 AND 2.8 AND THE CAO, NA2O, P2O5 AND SIO2 CONTENT OF THE COMBINED PHOSPHATE ROCK AND REAGENT MIXTURE BEING SUCH THAT THE MOL RATIO OF THESE CONSTITUENTS IN THE MOLAR FORMULA
Claim 2
Independent Claim
103 words
THE METHOD OF DEFLUORINATING PHOSPHATE ROCK WHICH COMPRISES SUBJECTING THE ROCK WITH A SILICA CONTENT OF FROM 2 TO 6% TO CALCINATION AT A TEMPERATURE OF AT LEAST 2600*F. WITHOUT SUBSTANTIAL FUSION IN THE PRESENCE OF WATER VAPOR AND OF A REAGENT MIXTURE CONSISTING ESSENTIALLY OF SODIUM CHLORIDE AND PHOSPHORIC ACID, THE MOLRATIO OF THE SODIUM AND PHOSPHORUS CONTENTS (CALCULATED AS NA2O AND P2O5 RESPECTIVELY) OF THE REAGENT MIXTURE BEING BETWEEN 1.6 AND 2.8 AND THE CAO, NA2O, P2O5 AND SIO2 CONTENT OF THE COMBINED PHOSPHATE ROCK AND REAGENT MIXTURE BEING SUCH THAT THE MOL RATIO OF THESE CONSTITUENTS IN THE MOLAR FORMULA
References Cited (Backward Citations)
US1878185A
Cited
US2093176A
Cited
US2337498A
Cited
US2288112A
Cited
US2442969A
Cited
US2556541A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-16 | 1961-12-16 | 1962-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-16 | 1965-12-16 | 1966-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-16 | 1969-12-16 | 1970-06-17 | $7700.00 | Window Closed / Lapsed |