US3856640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of hydrogen peroxide
Assignee: WRIGHT H CH
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Filing: 1972-05-30
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Granted: 1974-12-24
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Expires: 1992-05-30
Abstract
Abstract Dilute aqueous hydrogen peroxide solutions which are suitable for a variety of purification and disinfection applications are obtained economically by cathodic reduction of oxygen on an electrode composed of a gas-permeable but liquid-impermeable membrane comprising finely divided, highly porous carbon dispersed throughout a sintered fluorocarbon polymer, such as polytetrafluoroethylene.
Inventors
- 👤 K Halfar
- 👤 M Hitchman
- 👤 W Mehl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:10
CPC Classifications
B; B01; B01J; B01J19/00; B01J19/24; B01J19/2475; C; C25; C25B; C25B1/00; C25B1/01; C25B1/28; C25B1/30; C25B11/00; C25B11/04; C25B11/042; C25B11/043; C25B9/00; B01J2219/00; B01J2219/00049; B01J2219/00177
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
134 words
AN IMPROVED PROCESS FOR PRODUCING AQUEOUS HYDROGEN PEROXIDE INCLUDING THE STEP OF PASSING AN ELECTRIC CURRENT THROUGH AN AQUEOUS ELECTROLYTE BETWEEN AN ANODE AND A CATHODE WHEREIN ONE SURFACE OF SAID CATHODE IS IN CONTACT WITH SAID ELECTROLYTE AND ANOTHER SURFACE OF SAID CATHODE IS IN CONTACT WITH AN OXYGEN CONTAINING GAS, THEREIN THE IMPROVEMENT COMPRISES EMPLOYING AS SAID CATHODE A FLEXIBLE, GAS-PERMEABLE MEMBRANE HAVING A THICKNESS OF FROM ABOUT 0.1 TO ABOUT 2 MILLIMETERS AND A DENSITY OF FROM ABOUT 0.4 TO ABOUT 0.8 GRAMS PER CUBIC CENTIMETER, SAID MEMBRANE CONSISTING ESSENTIALLY OF FROM ABOUT 95 TO ABOUT 10 WEIGHT PERCENT OF FINELY DIVIDED, POROUS, HIGH SURFACE AREA CARBON DISPERSED THROUGH FROM ABOUT 5 TO ABOUT 90 WEIGHT PERCENT OF SINTERED, FINELY-DIVIDED PARTICLES OF A HYDROPHOBIC POLYMER OF A MONOMER OF THE FORMULA:
Claim 2
Dependent Claim
134 words
AN IMPROVED PROCESS FOR PRODUCING AQUEOUS HYDROGEN PEROXIDE INCLUDING THE STEP OF PASSING AN ELECTRIC CURRENT THROUGH AN AQUEOUS ELECTROLYTE BETWEEN AN ANODE AND A CATHODE WHEREIN ONE SURFACE OF SAID CATHODE IS IN CONTACT WITH SAID ELECTROLYTE AND ANOTHER SURFACE OF SAID CATHODE IS IN CONTACT WITH AN OXYGEN CONTAINING GAS, THEREIN THE IMPROVEMENT COMPRISES EMPLOYING AS SAID CATHODE A FLEXIBLE, GAS-PERMEABLE MEMBRANE HAVING A THICKNESS OF FROM ABOUT 0.1 TO ABOUT 2 MILLIMETERS AND A DENSITY OF FROM ABOUT 0.4 TO ABOUT 0.8 GRAMS PER CUBIC CENTIMETER, SAID MEMBRANE CONSISTING ESSENTIALLY OF FROM ABOUT 95 TO ABOUT 10 WEIGHT PERCENT OF FINELY DIVIDED, POROUS, HIGH SURFACE AREA CARBON DISPERSED THROUGH FROM ABOUT 5 TO ABOUT 90 WEIGHT PERCENT OF SINTERED, FINELY-DIVIDED PARTICLES OF A HYDROPHOBIC POLYMER OF A MONOMER OF THE FORMULA:
Claim 3
Dependent Claim
39 words
A method according to claim 1 wherein said carbon has a particle size in the range of from about 40 to about 55 millimicrons and a surface area of from about 40 to about 70 square meters per gram.
Claim 4
Dependent Claim
25 words
A method according to claim 1 wherein said polymer is of a monomer of the formula R2CF CF2 wherein R2 is chlorine, fluorine or trifluoromethyl.
Claim 5
Dependent Claim
26 words
A method according to claim 1 containing from about 45 to about 55 weight percent polymer and from about 55 to about 45 weight percent carbon.
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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |