US3654353A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating spent pulp liquors
Assignee: Weyerhaeuser Co
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Filing: 1964-10-23
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Granted: 1972-04-04
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Expires: 1984-10-23
Abstract
Abstract A METHOD OF RECOVERING VOLATILE, CONDENSIBLE ORGANIC ACIDS, PARTICULARLY ACETIC ACID, PRESENT IN THE VAPOR STREAM OBTAINED DURING EVAPORATION OF SPENT PULPING LIQUOR BY INJECTING INTO THE VAPOR STREAM A FINELY DIVIDED BASIC MATERIAL, SUCH AS SODIUM HYDROXIDE, TO CONVERT THE ACIDS IN THE VAPOR STREAM TO THEIR NON-VOLATILE SALTS. THE SALTS ARE SUBSEQUENTLY SEPARATED FROM THE RESIDUAL VAPOR STREAM, PRIMARILY WATER VAPOR, BY ENTRAINMENT.
Inventors
- 👤 Gerrit G De Haas
- 👤 Leslie H Clark
- 👤 Charles J Lang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:23
CPC Classifications
D; D21; D21C; D21C11/00; D21C11/0007; C; C07; C07C; C07C51/00; C07C51/42; C07C51/487
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-04 | 1979-10-04 | 1980-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-04 | 1983-10-04 | 1984-04-04 | $7700.00 | Window Closed / Lapsed |