US2711433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for extraction and recovery of aromatic hydrocarbons from hydrocarbon mixtures
Assignee: Dow Chemical Co
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Filing: 1952-06-02
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Granted: 1955-06-21
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Expires: 1972-06-02
Abstract
No abstract record available.
Inventors
- 👤 Poffenberger Noland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:09
CPC Classifications
C; C10; C10G; C10G21/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
106 words
IN A PROCESS IN WHICH A MIXTURE OF AROMATIC AND NON-AROMATIC HYDROCARBONS IS SUBJECTED TO COUNTERCURRENT MULTISTAGE EXTRACTION IN THE LIQUID PHASE WITH A SELECTIVE SOLVENT FOR AROMATIC HYDROCARBONS AND AN EXTRACT RICH IN AROMATIC HYDROCARBON IS WITHDRAWN FROM ONE END OF THE EXTRACTION SYSTEM, THE EXTRACT IS STRIPPED OF ITS HYDROCARBON CONTENT AND THE STRIPPED SOLVENT IS RETURNED TO THE OTHER END OF THE EXTRACTION SYSTEM, THE IMPROVEMENT WHICH CONSISTS IN: EFFECTING AT LEAST PART OF THE SAID STRIPPING OPERATION IN THE PRESENCE OF A SMALL BUT EFFECTIVE AMOUNT OF AN AGENT WHICH IS NON-REACTIVE WITH THE SOLVENT AND IS CAPABLE OF FORMING LOW-BOILING AZEOTROPES
Claim 2
Dependent Claim
106 words
IN A PROCESS IN WHICH A MIXTURE OF AROMATIC AND NON-AROMATIC HYDROCARBONS IS SUBJECTED TO COUNTERCURRENT MULTISTAGE EXTRACTION IN THE LIQUID PHASE WITH A SELECTIVE SOLVENT FOR AROMATIC HYDROCARBONS AND AN EXTRACT RICH IN AROMATIC HYDROCARBON IS WITHDRAWN FROM ONE END OF THE EXTRACTION SYSTEM, THE EXTRACT IS STRIPPED OF ITS HYDROCARBON CONTENT AND THE STRIPPED SOLVENT IS RETURNED TO THE OTHER END OF THE EXTRACTION SYSTEM, THE IMPROVEMENT WHICH CONSISTS IN: EFFECTING AT LEAST PART OF THE SAID STRIPPING OPERATION IN THE PRESENCE OF A SMALL BUT EFFECTIVE AMOUNT OF AN AGENT WHICH IS NON-REACTIVE WITH THE SOLVENT AND IS CAPABLE OF FORMING LOW-BOILING AZEOTROPES
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) | 1958-06-20 | 1958-12-20 | 1959-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-06-20 | 1962-12-20 | 1963-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-06-20 | 1966-12-20 | 1967-06-21 | $7700.00 | Window Closed / Lapsed |