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US4061548A
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US
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Electrolytic hydroquinone process
Assignee: Eastman Chemical Co
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Filing: 1976-06-07
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Granted: 1977-12-06
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Expires: 1996-06-07
Abstract
Abstract The process of electrochemically oxidizing phenol to hydroquinone is improved by the inclusion of chromium ion in the aqueous reaction medium.
Inventors
- 👤 Glenn C. Jones
- 👤 Ronald H. Meen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:01
CPC Classifications
C; C25; C25B; C25B3/00; C25B3/20; C25B3/23; C25B3/01; C25B3/07
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
44 words
In the process for the electrochemical oxidation of phenol to hydroquinone in an aqueous medium at a lead or lead-thallium alloy anode in an undivided cell, the improvement which comprises the inclusion in the aqueous medium of at least 50 ppm. of chromium ion.
Claim 2
Dependent Claim
44 words
In the process for the electrochemical oxidation of phenol to hydroquinone in an aqueous medium at a lead or lead-thallium alloy anode in an undivided cell, the improvement which comprises the inclusion in the aqueous medium of at least 50 ppm. of chromium ion.
Claim 3
Dependent Claim
24 words
In the process of claim 1 wherein the improvement comprises the inclusion in the aqueous medium of at least 300 ppm. of chromium ion.
Claim 4
Dependent Claim
60 words
In the process of claim 1 for the electrochemical oxidation of phenol to hydroquinone in an aqueous medium at a lead or lead-thallium alloy anode in an undivided cell, the improvement which comprises the inclusion in the aqueous medium of at least 300 ppm. of chromium ion while maintaining the concentration of hydroquinone at about 2.5 weight percent or less.
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) | 1980-12-05 | 1981-06-06 | 1981-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-05 | 1985-06-06 | 1985-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-05 | 1989-06-06 | 1989-12-06 | $7700.00 | Window Closed / Lapsed |