US2843457A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of oxy acids of phosphorus
Assignee: Occidental Chemical Corp
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Filing: 1954-11-17
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Granted: 1958-07-15
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Expires: 1974-11-17
Abstract
No abstract record available.
Inventors
- 👤 John C Pernert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:06
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/18; C01B25/185
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
52 words
THE PROCESS WHICH COMPRISES: FORMING A SOLUTION OF A SODIUM PHOSPHITE CONTAINING SODIUM BISULFATE, THE RATIO OF SODIUM ION TO SULFATE ION MOLE CONCENTRATION BEING ABOUT 2.0 TO 1.0; COOLING THIS SOLUTION TO A MINUS TWENTYTHREE DEGREE CENTRIGRADE; SEPARATING THE RESULTING CRYSTALS BY FILTRATION TO YIELD AN AQUEOUS SOLUTION OF PHOSPHOROUS ACID.
Claim 2
Dependent Claim
52 words
THE PROCESS WHICH COMPRISES: FORMING A SOLUTION OF A SODIUM PHOSPHITE CONTAINING SODIUM BISULFATE, THE RATIO OF SODIUM ION TO SULFATE ION MOLE CONCENTRATION BEING ABOUT 2.0 TO 1.0; COOLING THIS SOLUTION TO A MINUS TWENTYTHREE DEGREE CENTRIGRADE; SEPARATING THE RESULTING CRYSTALS BY FILTRATION TO YIELD AN AQUEOUS SOLUTION OF PHOSPHOROUS ACID.
Claim 3
Dependent Claim
57 words
THE PROCESS WHICH COMPRISES: FORMING A SOLUTION OF A SODIUM HYPOPHOSPHITE CONTAINING SULFURIC ACID, THE RATIO OF SODIUM ION TO SULFATE ION MOLE CONCENTRATION BEING BETWEEN ABOUT 3.0 AND 1.5 TO 1.0; COOLING THIS SOLUTION TO AT LEAST A MINUS FIFTEEN DEGREES CENTRIGRADE; SEPARATING THE RESULTING CRYSTALS BY FILTRATION TO YIELD AN AQUEOUS SOLUTION OF HYPOPHOSPHOROUS ACID.
Claim 4
Dependent Claim
57 words
THE PROCESS WHICH COMPRISES: FORMING A SOLUTION OF A SODIUM HYPOPHOSPHITE CONTAINING SULFURIC ACID, THE RATIO OF SODIUM ION TO SULFATE ION MOLE CONCENTRATION BEING BETWEEN ABOUT 3.0 AND 1.5 TO 1.0; COOLING THIS SOLUTION TO AT LEAST A MINUS FIFTEEN DEGREES CENTRIGRADE; SEPARATING THE RESULTING CRYSTALS BY FILTRATION TO YIELD AN AQUEOUS SOLUTION OF HYPOPHOSPHOROUS 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) | 1961-07-14 | 1962-01-13 | 1962-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-14 | 1966-01-13 | 1966-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-14 | 1970-01-13 | 1970-07-15 | $7700.00 | Window Closed / Lapsed |