US2504546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Superphosphate manufacture
Assignee: Davison Chemical Corp
•
Filing: 1947-01-28
•
Granted: 1950-04-18
•
Expires: 1967-01-28
Abstract
No abstract record available.
Inventors
- 👤 Edward H Wight
- 👤 Thomas O Tongue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:12
CPC Classifications
C; C05; C05B; C05B1/00; C05B1/02; Y; Y10; Y10S; Y10S71/00; Y10S71/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
146 words
A PROCESS FOR THE MANUFACTURE OF A SUPERPHOSPHATE FERTILIZER HAVING A LOW FLUORINE CONCENTRATION FROM PHOSPHATE ROCK COMPRISING MIXING FINELY DIVIDED PHOSPHATE ROCK WITH ABOUT 98% SULPHURIC ACID IN ACID TO ROCK RATIOS OF ABOUT THE STOICHIOMETRIC RATIO IN WHICH SULPHURIC ACID REACTS WITH THE ACID REACTIBLE COMPOUNDS IN THE ROCK AND WITH THE CALCIUM PHOSPHATE IN THE ROCK TO FORM MONO-CALCIUM PHOSPHATE, HEATING THE REACTION MIXTURE TO A TEMPERATURE OF ABOUT 250* F. TO 500*F. FOR ABOUT ONE HOUR, SAID MIXING AND HEATING STEPS VOLATILIZING ABOUT 60% TO 75% OF THE FLUORINE ORIGINALLY PRESENT IN THE PHOSPHATE ROCK, GRINDING THE HEATED PRODUCT, ADDING WATER THERETO IN QUANTITIES SUFFICIENT TO SUBSTANTIALLY COMPLETE THE REACTION BETWEEN THE SULPHURIC ACID AND PHOSPHATE ROCK TO EFFECT CONVERSION OF THE PHOSPHATE TO THE CITRATE SOLUBLE FORM, AND GRAINING THE MIXTURE AS THE WATER IS ADDED TO THE HEATED REACTION PRODUCT.
Claim 2
Dependent Claim
146 words
A PROCESS FOR THE MANUFACTURE OF A SUPERPHOSPHATE FERTILIZER HAVING A LOW FLUORINE CONCENTRATION FROM PHOSPHATE ROCK COMPRISING MIXING FINELY DIVIDED PHOSPHATE ROCK WITH ABOUT 98% SULPHURIC ACID IN ACID TO ROCK RATIOS OF ABOUT THE STOICHIOMETRIC RATIO IN WHICH SULPHURIC ACID REACTS WITH THE ACID REACTIBLE COMPOUNDS IN THE ROCK AND WITH THE CALCIUM PHOSPHATE IN THE ROCK TO FORM MONO-CALCIUM PHOSPHATE, HEATING THE REACTION MIXTURE TO A TEMPERATURE OF ABOUT 250* F. TO 500*F. FOR ABOUT ONE HOUR, SAID MIXING AND HEATING STEPS VOLATILIZING ABOUT 60% TO 75% OF THE FLUORINE ORIGINALLY PRESENT IN THE PHOSPHATE ROCK, GRINDING THE HEATED PRODUCT, ADDING WATER THERETO IN QUANTITIES SUFFICIENT TO SUBSTANTIALLY COMPLETE THE REACTION BETWEEN THE SULPHURIC ACID AND PHOSPHATE ROCK TO EFFECT CONVERSION OF THE PHOSPHATE TO THE CITRATE SOLUBLE FORM, AND GRAINING THE MIXTURE AS THE WATER IS ADDED TO THE HEATED REACTION PRODUCT.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-04-17 | 1953-10-17 | 1954-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-04-17 | 1957-10-17 | 1958-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-04-17 | 1961-10-17 | 1962-04-18 | $7700.00 | Window Closed / Lapsed |