US2528892A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Xylenes separation
Assignee: Standard Oil Co
•
Filing: 1948-08-25
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Granted: 1950-11-07
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Expires: 1968-08-25
Abstract
No abstract record available.
Inventors
- 👤 Arthur P Lien
- 👤 David A Mccaulay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:01
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/152
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
152 words
A PROCESS FOR THE CONCENTRATION OF INDIVIDUAL XYLENE ISOMERS FROM A SOLUTION OF AT LEAST TWO ISOMERIC XYLENES IN LIQUID HYDROGEN FLUORIDE AND BF3, SAID SOLUTION CONTAINING AT LEAST 1 MOL OF BF3 PER MOL OF CONTAINED XYLENES, WHICH PROCESS COMPRISES WITHDRAWING BF3 FROM SAID SOLUTION IN AN AMOUNT SUFFICIENT TO REDUCE THE CONCENTRATION OF BF3 IN SAID SOLUTION TO A VALUE BETWEEN ABOUT 0.5 AND ABOUT 0.9 MOL PER MOL OF AROMATIC HYDROCARBONS ORIGINALLY PRESENT IN SAID SOLUTION AND TO CONVERT SAID SOLUTION INTO TWO IMMISCRIBLE LIQUID LAYERS, ONE LIQUID LAYER CONSISTING ESSENTIALLY OF XYLENES IN A RATIO DIFFERENT FROM THEIR RATIO IN SAID SOLUTION AND THE OTHER LIQUID LAYER CONSISTING ESSENTIALLY OF A SECOND SOLUTION OF XYLENES IN LIQUID HYDROGEN FLUORIDE AND BF3, THE RATIO OF XYLENES IN SAID SECOND SOLUTION BEING DIFFERENT FROM THE RATIO OF XYLENES IN THE ORIGINAL SOLUTION, AND SEPARATING SAID LIQUID LAYERS FROM EACH OTHER.
Claim 2
Dependent Claim
152 words
A PROCESS FOR THE CONCENTRATION OF INDIVIDUAL XYLENE ISOMERS FROM A SOLUTION OF AT LEAST TWO ISOMERIC XYLENES IN LIQUID HYDROGEN FLUORIDE AND BF3, SAID SOLUTION CONTAINING AT LEAST 1 MOL OF BF3 PER MOL OF CONTAINED XYLENES, WHICH PROCESS COMPRISES WITHDRAWING BF3 FROM SAID SOLUTION IN AN AMOUNT SUFFICIENT TO REDUCE THE CONCENTRATION OF BF3 IN SAID SOLUTION TO A VALUE BETWEEN ABOUT 0.5 AND ABOUT 0.9 MOL PER MOL OF AROMATIC HYDROCARBONS ORIGINALLY PRESENT IN SAID SOLUTION AND TO CONVERT SAID SOLUTION INTO TWO IMMISCRIBLE LIQUID LAYERS, ONE LIQUID LAYER CONSISTING ESSENTIALLY OF XYLENES IN A RATIO DIFFERENT FROM THEIR RATIO IN SAID SOLUTION AND THE OTHER LIQUID LAYER CONSISTING ESSENTIALLY OF A SECOND SOLUTION OF XYLENES IN LIQUID HYDROGEN FLUORIDE AND BF3, THE RATIO OF XYLENES IN SAID SECOND SOLUTION BEING DIFFERENT FROM THE RATIO OF XYLENES IN THE ORIGINAL SOLUTION, AND SEPARATING SAID LIQUID LAYERS FROM EACH OTHER.
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) | 1953-11-06 | 1954-05-08 | 1954-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-06 | 1958-05-08 | 1958-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-06 | 1962-05-08 | 1962-11-07 | $7700.00 | Window Closed / Lapsed |