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US3645864A
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Process for the preparation of a p-amino phenol by the electrolytic reduction of nitrobenzene
Assignee: Worley Field Services Ltd
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Filing: 1970-05-28
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Granted: 1972-02-29
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Expires: 1990-05-28
Abstract
Abstract A process for the preparation of p-amino phenol and derivatives thereof, which process comprises reducing nitrobenzene electrolytically at a particulate electrode maintained at a cathode potential less negative than -0.40 volts with respect to a saturated calomel electrode, in an acidic medium at a temperature in the range of from 60* to 150* C. Preferably the cathode potential is in the range of from -0.25 to -0.35 volts with respect to a saturated calomel electrode.
Inventors
- 👤 Darryl William Lawson
- 👤 David Stanley Salter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:52
CPC Classifications
C; C25; C25B; C25B3/00; C25B3/20; C25B3/25; C25B3/01; C25B3/07; C25B3/09
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
65 words
A process as claimed in claim 1 wherein the particulate electrode is a restrained particulate bed electrode comprising a mass of substantially stationary discrete particles which are electrically conductive or which are at least partly electrically conductive or semi-conductive, and wherein a fluid comprising the electrolyte and/or the reactant or reactants for the electrochemical reaction are caused to flow through the mass of stationary particles.
Claim 2
Dependent Claim
34 words
A process as claimed in claim 1 wherein the particles forming the electrode are wholly conducting particles comprised of a material selected from the group consisting of copper, nickel, lead, Monel and copper/nickel alloys.
Claim 3
Dependent Claim
40 words
A process as claimed in claim 1 wherein the acidic medium forming the catholyte is selected from the group consisting of acetic acid, sulphuric acid, hydrochloric acid, phosphoric acid, perchloric acid, sodium hydrogen sulphate, potassium hydrogen sulphate and McKee salts.
Claim 4
Dependent Claim
21 words
A process as claimed in claim 4 wherein the acidic medium has an acid concentration in the range 3N to 8N.
Claim 5
Dependent Claim
34 words
A process as claimed in claim 1 wherein the electrolytic reduction is carried out at a cathode potential in the range of from -0.25 to -0.35 volts with respect to a saturated calomel electrode.
Claim 6
Dependent Claim
25 words
A process as claimed in claim 6 wherein the cathode potential is -0.300 + or - 0.10 volts with respect to a saturated calomel electrode.
Claim 7
Dependent Claim
75 words
A process for the preparation of p-amino phenol and derivatives thereof, which process comprises reducing nitrobenzene electrolytically at a particulate electrode wherein the size of the particles forming the electrode is in the range 200 to 1,000 Mu maintained at a cathode potential in the range of -0.25 to -0.40 volts with respect to a saturated calomel electrode, in an acidic medium at a temperature in the range of from about 90* to 120* C.
Claim 8
Dependent Claim
77 words
A process for the preparation of p-acetamido phenol which process comprises reducing nitrobenzene electrolytically in acetic acid having a concentration in the range 3N to 8N at a temperature in the range of from 60* to 150* C. at a particulate electrode wherein the size of the particles forming the electrode is in the range 200 to 1,000 Mu maintained at a cathode potential of from -0.25 to -0.35 volts with respect to a saturated calomel electrode.
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) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |