US2520716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of separating organic com
Assignee: —
•
Filing: —
•
Granted: 1950-08-29
•
Expires: 1967-08-29
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:24
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/152; C07C275/00; C07C275/02; C07C335/00; C07C335/02; C10; C10G; C10G21/00; C10G21/06; C10G21/12; C10G21/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A PROCESS OF SEPARATING A MIXTURE OF ORGANIC COMPOUNDS ONLY SOME OF WHICH ARE CAPABLE OF FORMING SOLID COMPLEXES WITH AN AGENT SELECTED FROM UREA AND THIOUREA, WHICH PROCESS COMPRISES TREATING SAID MIXTURE WITH A COMPLEX-FORMING AGENT THEREFOR SELECTED FROM UREA AND THIOUREA, AND MIXTURES THEREOF IN THE PRESENCE OF AN ACID ANHYDRIDE SELECTED FROM THE GROUP CONSISTING OF SULFUR DIOXIDE, NITROGEN DIOXIDE AND ACETIC ANHYDRIDE, THEREBY PRODUCING A SOLID COMPLEX OF SAID AGENT WITH THE COMPLEX-FORMING ORGANIC COMPOUNDS, AND SEPARATING THE RESULTING ORGANIC COMPLEX FROM THE REMAINING ORGANIC COMPOUNDS.
Claim 2
Dependent Claim
90 words
A PROCESS OF SEPARATING A MIXTURE OF ORGANIC COMPOUNDS ONLY SOME OF WHICH ARE CAPABLE OF FORMING SOLID COMPLEXES WITH AN AGENT SELECTED FROM UREA AND THIOUREA, WHICH PROCESS COMPRISES TREATING SAID MIXTURE WITH A COMPLEX-FORMING AGENT THEREFOR SELECTED FROM UREA AND THIOUREA, AND MIXTURES THEREOF IN THE PRESENCE OF AN ACID ANHYDRIDE SELECTED FROM THE GROUP CONSISTING OF SULFUR DIOXIDE, NITROGEN DIOXIDE AND ACETIC ANHYDRIDE, THEREBY PRODUCING A SOLID COMPLEX OF SAID AGENT WITH THE COMPLEX-FORMING ORGANIC COMPOUNDS, AND SEPARATING THE RESULTING ORGANIC COMPLEX FROM THE REMAINING ORGANIC COMPOUNDS.
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) | 1953-08-28 | 1954-02-27 | 1954-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-28 | 1958-02-27 | 1958-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-28 | 1962-02-27 | 1962-08-29 | $7700.00 | Window Closed / Lapsed |