US2955918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of phosphoric acid
Assignee: Monsanto Chemicals Ltd
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Filing: 1956-08-24
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Granted: 1960-10-11
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Expires: 1976-08-24
Abstract
No abstract record available.
Inventors
- 👤 Robert A Ruehrwein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:06
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/18; C01B25/234; C01B25/237; C01B25/238
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
THE METHOD OF REMOVING FROM PHOSPHORIC ACID TRIVALENT IRON IMPURITIES DISSOLVED THEREIN, WHICH METHOD COMPRISES DISSOLVING IN SAID PHOSPHORIC ACID SUFFICIENT CHLORIDE ION TO OBTAIN AT LEAST A 0.1 MOLAR CONCENTRATION THEREOF IN SAID ACID, CONTACTING SAID ACID WITH A WATERINSOLUBLE PHOSPHATE ESTER IN A LIQUID FORM SUFFICIENTLY IMMISCIBLE WITH SAID ACID AND IN SUFFICIENT AMOUNT TO FORM A SEPARATE LIQUID PHASE IN CONTACT WITH SAID ACID WHEREBY A SUBSTANTIAL PROPORTION OF SAID IRON IN THE ACID PHASE IS EXTRACTED FROM SAID ACID PHASE INTO THE LIQUID PHOSPHATE ESTER PHASE, AND THEREAFTER SEPARATING SAID ESTER PHASE FROM SAID ACID PHASE.
Claim 2
Independent Claim
100 words
THE METHOD OF REMOVING FROM PHOSPHORIC ACID TRIVALENT IRON IMPURITIES DISSOLVED THEREIN, WHICH METHOD COMPRISES DISSOLVING IN SAID PHOSPHORIC ACID SUFFICIENT CHLORIDE ION TO OBTAIN AT LEAST A 0.1 MOLAR CONCENTRATION THEREOF IN SAID ACID, CONTACTING SAID ACID WITH A WATERINSOLUBLE PHOSPHATE ESTER IN A LIQUID FORM SUFFICIENTLY IMMISCIBLE WITH SAID ACID AND IN SUFFICIENT AMOUNT TO FORM A SEPARATE LIQUID PHASE IN CONTACT WITH SAID ACID WHEREBY A SUBSTANTIAL PROPORTION OF SAID IRON IN THE ACID PHASE IS EXTRACTED FROM SAID ACID PHASE INTO THE LIQUID PHOSPHATE ESTER PHASE, AND THEREAFTER SEPARATING SAID ESTER PHASE FROM SAID ACID PHASE.
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) | 1963-10-11 | 1964-04-11 | 1964-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-10-11 | 1968-04-11 | 1968-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-10-11 | 1972-04-11 | 1972-10-11 | $7700.00 | Window Closed / Lapsed |