US5602294A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of o-xylene from p-xylene and m-xylene by extractive distillation
Assignee: Individual
•
Filing: 1995-05-31
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Granted: 1997-02-11
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Expires: 2015-05-31
Abstract
Abstract o-Xylene cannot be separated from p-xylene and m-xylene by conventional distillation or rectification because of the proximity of their boiling points. o-Xylene can be readily separated from mixtures of p-xylene and m-xylene by extractive distillation. Effective agents are o-cresol, dichloroacetic acid, methyl salicylate and 1-tetradecanol.
Inventors
- 👤 Lloyd Berg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:46
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
A method for recovering o-xylene from a mixture of o-xylene, p-xylene and m-xylene which comprises distilling a mixture of o-xylene, p-xylene and m-xylene in the presence of an extractive distillation agent, recovering the p-xylene and the m-xylene as overhead product and obtaining the o-xylene and the extractive distillation agent as bottoms product, wherein said extractive distillation agent consists of one material selected from the group consisting of o-cresol, dichloroacetic acid, methyl salicylate and 1-tetradecanol.
Claim 2
Independent Claim
74 words
A method for recovering o-xylene from a mixture of o-xylene, p-xylene and m-xylene which comprises distilling a mixture of o-xylene, p-xylene and m-xylene in the presence of an extractive distillation agent, recovering the p-xylene and the m-xylene as overhead product and obtaining the o-xylene and the extractive distillation agent as bottoms product, wherein said extractive distillation agent consists of one material selected from the group consisting of o-cresol, dichloroacetic acid, methyl salicylate and 1-tetradecanol.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-02-11 | 2000-08-12 | 2001-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-11 | 2004-08-12 | 2005-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-11 | 2008-08-12 | 2009-02-11 | $7700.00 | Window Closed / Lapsed |