Patent JPS56111284A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4528078A Expired / Lapsed US ⏱️ 0.0 years remaining

Nonsaturable microdryer

Assignee: ENERGY United States, Department of
•
Filing: 1984-05-23
•
Granted: 1985-07-09
•
Expires: 2004-05-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A nonsaturable microdryer is provided for electrolytically removing moisture from sealed containers, particularly electronic equipment. An electrode/electrolyte assembly is disposed within a channel between the interior and exterior of a sealed container. A catalytic barrier disposed between the interior of the sealed container and the electrode/electrolyte assembly prevents the build-up of explosive concentrations of hydrogen by converting back-diffusing hydrogen and oxygen back into water, which is then recycled. A semipermeable membrane disposed between the exterior of the sealed container and the electrode/electrolyte assembly allows selective removal of hydrogen and prevents intake of water.

Inventors

  • 👤 Tomas B. Hirschfeld

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 16:03
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/26; B01D53/32; B01D53/326

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 238 words
An apparatus for electrolytically removing moisture from a volume of gas enclosed by an associated sealed container, the apparatus comprising: (a) a first porous electrode; (b) a second porous electrode; (c) a hygroscopic solid electrolyte disposed between and forming electrical contacts witn the first porous electrode and the the second porous electrode to form an electrode/electrolyte assembly; (d) means defining a channel between the interior of the associated sealed container and the exterior of the associated sealed container, the electrode/electrolyte assembly being disposed in the channel; (e) a catalytic layer for enhancing the formation of water from hydrogen and oxygen, the catalytic layer being disposed inside the channel between the electrode/electrolyte assembly and the interior of the associated sealed container, and the catalytic layer spanning the channel such that any gas passing through the channel must pass through the catalytic layer; (f) a semipermeable membrane for selectively inhibiting the passage of water vapor and for selectively permitting the passage of hydrogen gas, the semipermeable membrane being disposed inside the channel between the electrode/electrolyte assembly and the exterior of the associated sealed container, and the semipermeable membrane spanning the channel such that any gas passing through the channel must pass through the semipermeable membrane; and (g) means for providing an alternating voltage across the hygroscopic solid electrolyte by way of the first and second porous electrodes for electrolyzing water, the alternating voltage having a predetermined magnitude, frequency, and waveform.
Claim 2
Independent Claim 238 words
An apparatus for electrolytically removing moisture from a volume of gas enclosed by an associated sealed container, the apparatus comprising: (a) a first porous electrode; (b) a second porous electrode; (c) a hygroscopic solid electrolyte disposed between and forming electrical contacts witn the first porous electrode and the the second porous electrode to form an electrode/electrolyte assembly; (d) means defining a channel between the interior of the associated sealed container and the exterior of the associated sealed container, the electrode/electrolyte assembly being disposed in the channel; (e) a catalytic layer for enhancing the formation of water from hydrogen and oxygen, the catalytic layer being disposed inside the channel between the electrode/electrolyte assembly and the interior of the associated sealed container, and the catalytic layer spanning the channel such that any gas passing through the channel must pass through the catalytic layer; (f) a semipermeable membrane for selectively inhibiting the passage of water vapor and for selectively permitting the passage of hydrogen gas, the semipermeable membrane being disposed inside the channel between the electrode/electrolyte assembly and the exterior of the associated sealed container, and the semipermeable membrane spanning the channel such that any gas passing through the channel must pass through the semipermeable membrane; and (g) means for providing an alternating voltage across the hygroscopic solid electrolyte by way of the first and second porous electrodes for electrolyzing water, the alternating voltage having a predetermined magnitude, frequency, and waveform.
Claim 3
Dependent Claim 16 words
The apparatus as recited in claim 1, wherein said hygroscopic solid electrolyte is an organic polymer.
Claim 4
Dependent Claim 18 words
The apparatus as recited in claim 2, wherein said organic polymer is a polymer of perfluorinated sulphonic acid.
Claim 5
Dependent Claim 16 words
The apparatus as recited in claim 3, wherein said polymer of perfluorinated sulphonic acid is Nafion.
Claim 6
Dependent Claim 21 words
The apparatus as recited in claim 1, wherein said first and second porous electrodes are made of a porous nickel alloy.
Claim 7
Dependent Claim 15 words
The apparatus as recited in claim 5, wherein said porous nickel alloy is sintered Monel.
Claim 8
Dependent Claim 48 words
The apparatus as recited in claim 1, wherein said first and second electrodes are electrically insulated from said associated sealed container and wherein said predetermined waveform of said alternating voltage is square such that said alternating voltage varies between the positive and negative values of said predetermined magnitude.
Claim 9
Dependent Claim 17 words
The apparatus as recited in claim 7, wherein said predetermined magnitude is at least about 1.3 volts.
Claim 10
Dependent Claim 48 words
The apparatus as recited in claim 8, wherein said hygroscopic solid electrolyte is a Nafion sheet between about 170 and 180 μm thick, wherein said predetermined magnitude is between about 1.3 volts and 2.5 volts, and wherein said predetermined frequency is between about 8 kHz and 12 kHz.
Claim 11
Dependent Claim 74 words
The apparatus as recited in claim 1, wherein at least one of said first or second porous electrodes is electrically insultated from said associated sealed container to form an insulated porous electrode, and wherein said predetermined waveform of said alternating voltage is square such that said alternating voltage varies between ground and a predetermined negative value, said alternating voltage periodically reducing the electrical potential of the insulated porous electrode to the predetermined negative value.
Claim 12
Dependent Claim 17 words
The apparatus recited in claim 9, wherein said predetermined negative value is at most about -1.3 volts.
Claim 13
Independent Claim 183 words
A method of dehumidifying a sealed container comprising the steps of: (a) providing a channel between the exterior and interior of the sealed container; (b) electrolytically transforming water into hydrogen and oxygen by an electrode/electrolyte assembly disposed inside the channel, the electrode/electrolyte assembly having a hygroscopic electrolyte; (c) selectively removing a portion of the hydrogen gas generated by the electrode/electrolyte assembly from the interior of the sealed container and selectively inhibiting the influx of water from the exterior of the sealed container to the interior of the sealed container by a semipermeable membrane, the semipermeable membrane being disposed in the channel between the electrode/electrolyte assembly and the exterior of the sealed container; and (d) catalytically transforming hydrogen generated by the electrode/electrolyte assembly and diffusing toward the interior of the sealed container back into water by a catalytic layer disposed inside the channel betwenn the electrode/electrolyte assembly and the interior of the sealed container, a portion of said water formed by the catalytic layer being re-absorbed by the hygroscopic electrolyte of the electrode/electrolyte assembly where said water is electrolytically transformed into hydrogen and oxygen.
Claim 14
Independent Claim 183 words
A method of dehumidifying a sealed container comprising the steps of: (a) providing a channel between the exterior and interior of the sealed container; (b) electrolytically transforming water into hydrogen and oxygen by an electrode/electrolyte assembly disposed inside the channel, the electrode/electrolyte assembly having a hygroscopic electrolyte; (c) selectively removing a portion of the hydrogen gas generated by the electrode/electrolyte assembly from the interior of the sealed container and selectively inhibiting the influx of water from the exterior of the sealed container to the interior of the sealed container by a semipermeable membrane, the semipermeable membrane being disposed in the channel between the electrode/electrolyte assembly and the exterior of the sealed container; and (d) catalytically transforming hydrogen generated by the electrode/electrolyte assembly and diffusing toward the interior of the sealed container back into water by a catalytic layer disposed inside the channel betwenn the electrode/electrolyte assembly and the interior of the sealed container, a portion of said water formed by the catalytic layer being re-absorbed by the hygroscopic electrolyte of the electrode/electrolyte assembly where said water is electrolytically transformed into hydrogen and oxygen.
Claim 15
Dependent Claim 84 words
The method as recited in claim 10, wherein the step of electrolytically transforming further includes the steps of: (a) providing an electrode/electrolyte assembly with a first porous electrode, a second porous electrode, and a solid hygroscopic electrolyte sandwiched between and making electrical contact with the first porous electrode and the second porous electrode; and (b) applying alternating voltage across the solid electrolyte by way of the first and second porous electrodes for electrolyzing water, the alternating voltage having a predetermined magnitude, frequency, and waveform.

References Cited (Backward Citations)

US3086924A Cited
US3188283A Cited
US3474023A Cited
US3475302A Cited
US3400069A Cited
US4050995A Cited
US4094652A Cited
US4332663A Cited
US4247988A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-07-08 1989-01-07 1989-07-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-07-08 1993-01-07 1993-07-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-07-08 1997-01-07 1997-07-09 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag