US5176889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for treatment of NF3 gas
Assignee: Air Water Inc
•
Filing: 1992-01-30
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Granted: 1993-01-05
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Expires: 2012-01-30
Abstract
Abstract In accordance with this invention, a waste gas containing toxic NF3 gas is contacted with a honeycomb structure of a carbonaceous material to thereby convert NF3 into nontoxic CF4 and H2 gases with high efficiency.
Inventors
- 👤 Akira Yoshino
- 👤 Takakazu Tomoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:13
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/02; C07; C07C; C07C17/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
57 words
A method for converting gaseous NF 3 into CF 4 and N 2 gases, comprising passing a NF 3 containing gas through a multiplicity of openings in a honeycomb structure of carbon at a temperature of about 300° C. to about 600° C., whereby said NF 3 containing gas reacts with walls of carbon defining said openings.
Claim 2
Independent Claim
57 words
A method for converting gaseous NF 3 into CF 4 and N 2 gases, comprising passing a NF 3 containing gas through a multiplicity of openings in a honeycomb structure of carbon at a temperature of about 300° C. to about 600° C., whereby said NF 3 containing gas reacts with walls of carbon defining said openings.
Claim 3
Dependent Claim
23 words
The method for treating NF 3 gas as claimed in claim 1 wherein said openings have a diameter of 0.1 to 15 mm.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-01-05 | 1996-07-06 | 1997-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-01-05 | 2000-07-06 | 2001-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-01-05 | 2004-07-06 | 2005-01-05 | $7700.00 | Window Closed / Lapsed |