US2889256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of hexamethylene diamine
Assignee: Solutia Inc
•
Filing: 1956-04-04
•
Granted: 1959-06-02
•
Expires: 1976-04-04
Abstract
No abstract record available.
Inventors
- 👤 Charles R Campbell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:26
CPC Classifications
B; B01; B01D; B01D3/00; B01D3/34; B01D3/343; C; C07; C07C; C07C209/00; C07C209/82; C07C209/84; C07C209/86
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
A METHOD FOR THE PRODUCTION OF HEXAMETHYLENE DIAMINE WHICH COMPRISES REMOVING DISSOLVED AMMONIA BY CONTACTING LIQUID HEXAMETHYLENE DIAMINE CONTAINING DISSOLVED AMMONIA WITH AN INERT GAS SELECTED FROM THE GROUP CONSISTING OF NITROGEN, CARBON DIOXIDE FREE AIR, AND THE PRODUCT OF THE COMBUSTION OF METHAN E WHICH HAS BEEN FREED FROM CARBON DIOXIDE IN AN AMOUNT OF FROM 0.001 IS 15 CUBIC FEET PER POUND OF LIQUID HEXAMETHYLENE DIAMINE.
Claim 2
Independent Claim
68 words
A METHOD FOR THE PRODUCTION OF HEXAMETHYLENE DIAMINE WHICH COMPRISES REMOVING DISSOLVED AMMONIA BY CONTACTING LIQUID HEXAMETHYLENE DIAMINE CONTAINING DISSOLVED AMMONIA WITH AN INERT GAS SELECTED FROM THE GROUP CONSISTING OF NITROGEN, CARBON DIOXIDE FREE AIR, AND THE PRODUCT OF THE COMBUSTION OF METHAN E WHICH HAS BEEN FREED FROM CARBON DIOXIDE IN AN AMOUNT OF FROM 0.001 IS 15 CUBIC FEET PER POUND OF LIQUID HEXAMETHYLENE DIAMINE.
References Cited (Backward Citations)
US1244903A
Cited
US2184923A
Cited
US2255114A
Cited
US2353441A
Cited
US2522529A
Cited
GB731819A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-06-01 | 1962-12-01 | 1963-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-01 | 1966-12-01 | 1967-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-01 | 1970-12-01 | 1971-06-02 | $7700.00 | Window Closed / Lapsed |