US2744927A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solvent extraction of black liquor
Assignee: Sonoco Products Co
•
Filing: 1952-11-28
•
Granted: 1956-05-08
•
Expires: 1972-11-28
Abstract
No abstract record available.
Inventors
- 👤 James E Copenhaver
- 👤 Jr William A Biggs
- 👤 William H Baxley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:34
CPC Classifications
D; D21; D21C; D21C11/00; D21C11/0007; C; C07; C07C; C07C51/00; C07C51/42; C07C51/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
A PROCESS OF TREATING BLACK LIQUOR TO EFFECT THE REMOVAL THEREFROM OF ACETIC ACID, COMPRISING CONCENTRATING SAID BLACK LIQUOR TO A SOLIDS CONTENT OF APPROXIMATELY 25% TO 60%, ACIDIFYING THE CONCENTRATED BLACK LIQUOR WITH SULFURIC ACID, AND EXTRACTING THE CONCENTRATED AND ACIDIFIED BLACK LIQUOR WITH A SOLUTION COMPOSED OF 70% ISOPROPYL ACETATE AND 30% ISOPROPANOL AND SEPARATING THE ACETIC ACID FROM THE EXTRACTING SOLVENT.
Claim 2
Dependent Claim
64 words
A PROCESS OF TREATING BLACK LIQUOR TO EFFECT THE REMOVAL THEREFROM OF ACETIC ACID, COMPRISING CONCENTRATING SAID BLACK LIQUOR TO A SOLIDS CONTENT OF APPROXIMATELY 25% TO 60%, ACIDIFYING THE CONCENTRATED BLACK LIQUOR WITH SULFURIC ACID, AND EXTRACTING THE CONCENTRATED AND ACIDIFIED BLACK LIQUOR WITH A SOLUTION COMPOSED OF 70% ISOPROPYL ACETATE AND 30% ISOPROPANOL AND SEPARATING THE ACETIC ACID FROM THE EXTRACTING SOLVENT.
References Cited (Backward Citations)
US2129684A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-05-08 | 1959-11-07 | 1960-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-05-08 | 1963-11-07 | 1964-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-05-08 | 1967-11-07 | 1968-05-08 | $7700.00 | Window Closed / Lapsed |