US2598449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of naphthalene
Assignee: Midland Tar Distillers Ltd
•
Filing: 1948-08-02
•
Granted: 1952-05-27
•
Expires: 1968-08-02
Abstract
No abstract record available.
Inventors
- 👤 Scott Roland
- 👤 Eric H Joscelyne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:06
CPC Classifications
B; B01; B01D; B01D9/00; B01D9/0004; B01D9/0013; B01D9/004; B01D9/005; C; C07; C07C; C07C7/00; C07C7/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
145 words
A CONTINUOUS PROCESS FOR PURIFYING CRUDE NAPHTHALENE COMPRISING CONTINUOUSLY INTRODUCING CRUDE MOLTEN NAPHTHALENE INTO A FLOWING STREAM OF PRECIPITATING LIQUID IN WHICH NAPHTHALENE IS OF LOW SOLUBILITY AND WHICH IS ALSO A SOLVENT FOR THE IMPURITIES AND IS AT A TEMPERATURE OF THE ORDER OF 20-40* C. TO CAUSE NAPHTHALENE CRYSTALS TO FORM AT ONCE, CAUSING NAPHTHALENE FLOW A SUFFICIENT DISTANCE TO ALLOW THE CRYSTALS TO INCREASE IN SIZE TO NOT LESS THAN 2 MILLIMETERS AND AT THE SAME TIME PREVENTING AGGOLMERATION OF THE CRYSTALS BY AGITATING THE FLOWING MIXTURE, SEPARATING THE CRYSTALS FROM SAID MIXTURE BY CONVEYING SAID CRYSTALS UPWARDLY OUT OF SAID MIXTURE, WASHING SAID CRYSTALS BEING SO CONVEYED WITH A DOWNWARDLY FLOWING STREAM OF THE SAME LIQUID, DIRECTING SAID DOWNWARDLY FLOWING STREAM INTO THE LIQUID STREAM FROM WHICH SAID CRYSTALS ARE UPWARDLY CONVEYED TO MIX THEREWITH, AND REMOVING THE RESULTANT MIXED STREAM.
Claim 2
Dependent Claim
145 words
A CONTINUOUS PROCESS FOR PURIFYING CRUDE NAPHTHALENE COMPRISING CONTINUOUSLY INTRODUCING CRUDE MOLTEN NAPHTHALENE INTO A FLOWING STREAM OF PRECIPITATING LIQUID IN WHICH NAPHTHALENE IS OF LOW SOLUBILITY AND WHICH IS ALSO A SOLVENT FOR THE IMPURITIES AND IS AT A TEMPERATURE OF THE ORDER OF 20-40* C. TO CAUSE NAPHTHALENE CRYSTALS TO FORM AT ONCE, CAUSING NAPHTHALENE FLOW A SUFFICIENT DISTANCE TO ALLOW THE CRYSTALS TO INCREASE IN SIZE TO NOT LESS THAN 2 MILLIMETERS AND AT THE SAME TIME PREVENTING AGGOLMERATION OF THE CRYSTALS BY AGITATING THE FLOWING MIXTURE, SEPARATING THE CRYSTALS FROM SAID MIXTURE BY CONVEYING SAID CRYSTALS UPWARDLY OUT OF SAID MIXTURE, WASHING SAID CRYSTALS BEING SO CONVEYED WITH A DOWNWARDLY FLOWING STREAM OF THE SAME LIQUID, DIRECTING SAID DOWNWARDLY FLOWING STREAM INTO THE LIQUID STREAM FROM WHICH SAID CRYSTALS ARE UPWARDLY CONVEYED TO MIX THEREWITH, AND REMOVING THE RESULTANT MIXED STREAM.
References Cited (Backward Citations)
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Cited
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US1810217A
Cited
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Cited
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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) | 1955-05-27 | 1955-11-26 | 1956-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-05-27 | 1959-11-26 | 1960-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-05-27 | 1963-11-26 | 1964-05-27 | $7700.00 | Window Closed / Lapsed |