Patent US2557258A successfully refreshed from Google Patents.
US2557258A
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Process for removal of impurities from dicyanobutene
Assignee: EIDP Inc
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Filing: 1950-02-23
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Granted: 1951-06-19
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Expires: 1970-02-23
Abstract
No abstract record available.
Inventors
- 👤 William H Calkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:53
CPC Classifications
C; C07; C07C; C07C255/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
THE PROCESS FOR SEPARATING COPPER COMPOUNDS FROM MIXTURES CONTAINING SUCH COMPOUNDS DISSOLVED IN 1,4-DICYANO-2-BUTENE, SAID COMPOUNDS BEING THE COPPER-CONTAINING PRODUCTS WHICH ARE FORMED BY REACTION OF HCN WITH DICHLOROBUTENE UNDER AQUEOUS ACIDIC CONDITIONS IN THE LIQUID PHASE IN THE PRESENCE OF A DISSOLVED COPPER-CONTAINING CATALYST, WHICH COMPRISES EXTRACTING THE SAID COMPOUNDS FROM THE SAID 1,4DICYANO-2-BUTENE WITH AQUEOUS HCN AT A PH WITHIN THE RANGE OF 4.0 TO 7.0.
Claim 2
Dependent Claim
68 words
THE PROCESS FOR SEPARATING COPPER COMPOUNDS FROM MIXTURES CONTAINING SUCH COMPOUNDS DISSOLVED IN 1,4-DICYANO-2-BUTENE, SAID COMPOUNDS BEING THE COPPER-CONTAINING PRODUCTS WHICH ARE FORMED BY REACTION OF HCN WITH DICHLOROBUTENE UNDER AQUEOUS ACIDIC CONDITIONS IN THE LIQUID PHASE IN THE PRESENCE OF A DISSOLVED COPPER-CONTAINING CATALYST, WHICH COMPRISES EXTRACTING THE SAID COMPOUNDS FROM THE SAID 1,4DICYANO-2-BUTENE WITH AQUEOUS HCN AT A PH WITHIN THE RANGE OF 4.0 TO 7.0.
References Cited (Backward Citations)
US2448755A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-06-18 | 1954-12-18 | 1955-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-18 | 1958-12-18 | 1959-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-18 | 1962-12-18 | 1963-06-19 | $7700.00 | Window Closed / Lapsed |