US2798089A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sulfonation of benzene
Assignee: Tennessee Corp
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Filing: 1954-11-29
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Granted: 1957-07-02
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Expires: 1974-11-29
Abstract
No abstract record available.
Inventors
- 👤 Samuel L Norwood
- 👤 Walter H C Rueggeberg
- 👤 Thomas W Sauls
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:17
CPC Classifications
C; C07; C07C; C07C309/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
97 words
IN THE SULFONATION OF BENZENE WITH SULFUR TRIOXIDE DISSOLOVED IN LIQUID SULFUR DIOXIDE AT ATMOSPHERIC PRESSURE TO PRODUCE SUBSTANTIALLY PURE BENZENE SULFONIC ACID, THE PROCESS OF MAINTAINING A LIQUID REACTION MIXTURE WHICH COMPRISES REACTING 0.5-0.8 MOL BENZENE WITH ONE MOLE OF SULFUR TROIXIDE DISSOLVED IN LIQUID SULFUR DIOXIDE AT ABOUT -9*C., SUBSEQUENTLY EVAPORATING THE LIQUID SULFUR DIOXIDE FROM THE SYSTEM UNTIL THE TEMPERATURE REACHES 10-20*C. AT ATMOSPHERIC PRESSURE, AND ADDING THE REMAINING 0.5-0.2 MOLE BENZENE QUICKLY INTO THIS MIXTURE ALLOWING THE HEAT OF REACTION TO RAISE THE TEMPERATURE TO APPROXIMATELY 50-70*C. AT WHICH POINT SULFONATION IS COMPLETE.
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) | 1960-07-01 | 1960-12-31 | 1961-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-01 | 1964-12-31 | 1965-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-01 | 1968-12-31 | 1969-07-02 | $7700.00 | Window Closed / Lapsed |