Patent US2656266A successfully refreshed from Google Patents.
US2656266A
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Method for reducing the acidity of nitric acid-calcium nitrate compositions containing phosphate ions
Assignee: Norsk Hydro Elektrisk Kvaelstof AS
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Filing: 1949-03-15
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Granted: 1953-10-20
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Expires: 1969-03-15
Abstract
No abstract record available.
Inventors
- 👤 Calmeyer Reidar Bang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:50
CPC Classifications
C; C05; C05C; C05C5/00; C05C5/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
A PROCESS FOR REDUCING THE ACIDITY OF A NITRIACID-CALCIUM-NITRATE COMPOSITION IN DISSOLVE FORM CONTAINING PHOSPHATE IONS AND UP TO 0.3% OF FLUORIDE IONS WITH CALCIUM CARBONATE COMPRISING THE STEPS OF TREATING A FIRST PORTION OF SAID NITRIC ACID CALCIUM NITRATE COMPOSITION WITH AN AQUEOUS SOLUTION OF A BASE SELECTED FROM THE GROUP CONSISTING OF CALCIUM OXIDE, CALCIUM HYDROXIDE, ALKALI METAL HYDROXIDE, AMMONIUM HYDROXIDE AND AMMONIUM CARBONATE TO OBTAIN THEREBY A PH VALUE ABOVE 2.5 AND SHORT OF NEUTRALIZATION AND THEREAFTER SIMULTANEOUSLY ADDING TO SAID FIRST TREATED PORTION ADDITIONAL QUANTITIES OF SAID NITRIC ACIDCALCIUM NITRATE COMPOSITION TOGETHER WITH FINELY DIVIDED CALCIUM CARBONATE, SAID CALCIUM CARBONATE BEING ADDED IN AMOUNTS AT LEAST EQUILAVENT TO THE ACID IN SAID ADDED NITRIC ACID-CALCIUM NITRATE COMPOSITION, TO OBTAIN THEREBY A RESULTING PH VALUE BETWEEN 3 AND 4, WITHOUT THE FURTHER ADDITION OF A BASIC HYDROXIDE.
Claim 2
Dependent Claim
140 words
A PROCESS FOR REDUCING THE ACIDITY OF A NITRIACID-CALCIUM-NITRATE COMPOSITION IN DISSOLVE FORM CONTAINING PHOSPHATE IONS AND UP TO 0.3% OF FLUORIDE IONS WITH CALCIUM CARBONATE COMPRISING THE STEPS OF TREATING A FIRST PORTION OF SAID NITRIC ACID CALCIUM NITRATE COMPOSITION WITH AN AQUEOUS SOLUTION OF A BASE SELECTED FROM THE GROUP CONSISTING OF CALCIUM OXIDE, CALCIUM HYDROXIDE, ALKALI METAL HYDROXIDE, AMMONIUM HYDROXIDE AND AMMONIUM CARBONATE TO OBTAIN THEREBY A PH VALUE ABOVE 2.5 AND SHORT OF NEUTRALIZATION AND THEREAFTER SIMULTANEOUSLY ADDING TO SAID FIRST TREATED PORTION ADDITIONAL QUANTITIES OF SAID NITRIC ACIDCALCIUM NITRATE COMPOSITION TOGETHER WITH FINELY DIVIDED CALCIUM CARBONATE, SAID CALCIUM CARBONATE BEING ADDED IN AMOUNTS AT LEAST EQUILAVENT TO THE ACID IN SAID ADDED NITRIC ACID-CALCIUM NITRATE COMPOSITION, TO OBTAIN THEREBY A RESULTING PH VALUE BETWEEN 3 AND 4, WITHOUT THE FURTHER ADDITION OF A BASIC HYDROXIDE.
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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) | 1956-10-19 | 1957-04-20 | 1957-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-10-19 | 1961-04-20 | 1961-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-10-19 | 1965-04-20 | 1965-10-20 | $7700.00 | Window Closed / Lapsed |