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Patent US3118731A successfully refreshed from Google Patents.
US3118731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Svanoe
Assignee: —
•
Filing: 1959-10-28
•
Granted: 1964-01-21
•
Expires: 1979-10-28
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:26
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/18; C01B25/234; C01B25/2343; C01B25/22; Y; Y10; Y10S; Y10S159/00; Y10S159/19; Y10S159/25
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
IN A IMPROVED PROCESS FOR THE PREPARATION OF PHOSPHORIC ACID BY THE WET PROCESS WHEREIN THE CONCENTRATION OF PHOSPHORIC ACID IS EFFECTED WITH REDUCED DEPOSITION OF CALCIUM SULFATE AND FLUOSILICATE CRYSTALS AND WITH REDUCED CORROSION, THE STEPS WHICH COMPRISE: A. DISSOLVING TRICALCIUM PHOSPHATE FROM PHOSPHATE ROCK, WITH PHOSPHORIC ACID, B. ADDING SULFURIC ACID TO THE RESULTING SOLUTION TO EFFECT REACTIONS IN ACCORD WITH THE FOLLOWING EQUATIONS AND TO GIVE, AT LEAST, 1% BY WEIGHT OF EXCESS SULFURIC ACID;
Claim 2
Dependent Claim
78 words
IN A IMPROVED PROCESS FOR THE PREPARATION OF PHOSPHORIC ACID BY THE WET PROCESS WHEREIN THE CONCENTRATION OF PHOSPHORIC ACID IS EFFECTED WITH REDUCED DEPOSITION OF CALCIUM SULFATE AND FLUOSILICATE CRYSTALS AND WITH REDUCED CORROSION, THE STEPS WHICH COMPRISE: A. DISSOLVING TRICALCIUM PHOSPHATE FROM PHOSPHATE ROCK, WITH PHOSPHORIC ACID, B. ADDING SULFURIC ACID TO THE RESULTING SOLUTION TO EFFECT REACTIONS IN ACCORD WITH THE FOLLOWING EQUATIONS AND TO GIVE, AT LEAST, 1% BY WEIGHT OF EXCESS SULFURIC ACID;
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) | 1967-01-20 | 1967-07-22 | 1968-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-01-20 | 1971-07-22 | 1972-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-01-20 | 1975-07-22 | 1976-01-21 | $7700.00 | Window Closed / Lapsed |