Patent US3555082A successfully refreshed from Google Patents.
US3555082A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for isolating acrylic acid from the reaction gases obtained by oxidation of propylene or acrolein
Assignee: Knapsack AG
•
Filing: 1967-11-15
•
Granted: 1971-01-12
•
Expires: 1987-11-15
Abstract
Abstract PROCESS FOR ISOLATING ACRYLIC ACID FROM HOT REACTION GASES OBTAINED BY OXIDATION OF PROPYLENE TO ACROLEIN COMPRISING THE STEPS OF COOLING THE REACTION GAS DOWN TO A TEMPERATURE BETWEEN ABOUT 90 AND 200*C., EXTRACTING THEREAFTER THE GAS IN COUNTER-CURRENT FASHION WITH AN ESTER OF AN ALIPHATIC OR AROMATIC MONOCARBOXYLIC OR DICARBOXYLIC ACID OR WITH TRIBUTYL OR TRICRESYL PHOSPHATE, SUBJECTING RESULTING EXTRACT TO DISTILLATION TO REMOVE ACRYLIC ACID IN THE FORM OF A CONCENTRATED AQUEOUS SOLUTION, AND USING REMAINING DISTILLATION RESIDUE FOR THE EXTRACTION OF FURTHER ACRYLIC ACID-CONTAINING REACTION GAS.
Inventors
- 👤 Kurt Sennewald
- 👤 Alfred Hauser
- 👤 Winfried Lork
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:07
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/25; C07C51/252; C07C51/42; C07C51/48
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |