US3363978A
Expired / Lapsed
US
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Process for recovering phosphoric acid from aqueous solutions containing nitric acid and phosphoric acid
Assignee: Stamicarbon BV
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Filing: 1964-10-06
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Granted: 1968-01-16
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Expires: 1984-10-06
Abstract
No abstract record available.
Inventors
- 👤 Rooij Abraham H De
- 👤 Elmendorp Jan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:23
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/18; C01B25/22; C01B21/00; C01B21/20; C01B21/38; C01B21/46; C01B25/234
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
98 words
A PROCESS FOR RECOVERING PHOSPHORIC ACID FROM AQUEOUS SOLUTIONS CONTAINING NITRIC ACID AND PHOSPHORIC ACID, WHICH COMPRISES EXTRACTING THE SOLUTION AT A WATER CONTENT OF AT MOST 70% BY WEIGHT AND AT LEAST 40% BY WEIGHT, USING AN EXTRACTING AGENT SELECTED FROM THE GROUP CONSISTING OF POORLY WATER-MISCIBLE LOWER ALIPHATIC KETONES AND LOWER ALIPHATIC ETHERS, THE WEIGHT RATIO BETWEEN THE SOLUTION AND THE EXTRACTING AGEN BEING KEPT BETWEEN THE LIMITS 1:1 AND 1:3, WHEREBY NITRIC ACID IS PREFERENTIALLY TAKEN UP BY SAID EXTRACTING AGENT AND CONCENTRATING THE RESULTING AQUEOUS SOLUTION OF PHOSPHORIC ACID ESSENTIALLY FREE FROM NITRIC ACID.
Claim 2
Dependent Claim
98 words
A PROCESS FOR RECOVERING PHOSPHORIC ACID FROM AQUEOUS SOLUTIONS CONTAINING NITRIC ACID AND PHOSPHORIC ACID, WHICH COMPRISES EXTRACTING THE SOLUTION AT A WATER CONTENT OF AT MOST 70% BY WEIGHT AND AT LEAST 40% BY WEIGHT, USING AN EXTRACTING AGENT SELECTED FROM THE GROUP CONSISTING OF POORLY WATER-MISCIBLE LOWER ALIPHATIC KETONES AND LOWER ALIPHATIC ETHERS, THE WEIGHT RATIO BETWEEN THE SOLUTION AND THE EXTRACTING AGEN BEING KEPT BETWEEN THE LIMITS 1:1 AND 1:3, WHEREBY NITRIC ACID IS PREFERENTIALLY TAKEN UP BY SAID EXTRACTING AGENT AND CONCENTRATING THE RESULTING AQUEOUS SOLUTION OF PHOSPHORIC ACID ESSENTIALLY FREE FROM NITRIC 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) | 1971-01-15 | 1971-07-17 | 1972-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-01-15 | 1975-07-17 | 1976-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-01-15 | 1979-07-17 | 1980-01-16 | $7700.00 | Window Closed / Lapsed |