US3246449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of helium
Assignee: Union Carbide Corp
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Filing: 1959-06-09
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Granted: 1966-04-19
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Expires: 1979-06-09
Abstract
No abstract record available.
Inventors
- 👤 Silviu A Stern
- 👤 Paul H Mohr
- 👤 Paul J Gareis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:29
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/30; B01D71/32; C; C01; C01B; C01B23/00; B01D2317/00; B01D2317/02; B01D2317/022
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
100 words
A PROCESS FOR RECOVERING HELIUM FROM A GAS MIXTURE COMPRISING HELIUM AND AT LEAST ONE GASEOUS HYDROCARBON, COMPRISING THE STEPS: (1) CONTACTING SAID GAS MIXTURE WITH ONE SIDE OF A THIN, NON-POROUS, PLASTIC MEMBRANE COMPRISED ESSENTIALLY OF A FILM-FORMING MATERIAL SELECTED FROM THE GROUP CONSISTING OF A POLYTETRAFLUOROETHYLENE, POLYTRIBLUOROCHLOROETHYLENE, A COPOLYMER OF POLYETRAFLUOROETHYLENE AND HEXAFLUOROPROPYLENE, AND A COPOLYMER OF VINYLIDENE FLUORIDE AND HEXAFLUOORPROPYLENE; (2) PERMEATING A PORTION OF SAID GAS MIXTURE THROUGH SAID MEMBRANE, THE PERMEATED PORTION CONTAING A GREATER CONCENTRATION OF HELIUM THAN THE GAS MIXTURE; AND (3) REMOVING THE PERMEATED GAS FROM THE OPPOSITE SIDE OF SAID MEMBRANE.
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) | 1969-04-18 | 1969-10-18 | 1970-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-04-18 | 1973-10-18 | 1974-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-04-18 | 1977-10-18 | 1978-04-19 | $7700.00 | Window Closed / Lapsed |