US4091081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of nitrogen trifluoride
Assignee: Air Products and Chemicals Inc
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Filing: 1977-04-19
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Granted: 1978-05-23
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Expires: 1997-04-19
Abstract
Abstract Nitrogen trifluoride is prepared by passing elemental fluorine in intimate contact with liquid phase ammonium acid fluoride maintained at a temperature above its melting point but below about 400 DEG F for a time sufficient to effect reaction. Generally, ammonia is injected into the ammonium acid fluoride along with the fluorine to maintain a molar ratio of by-product hydrogen fluoride to ammonia of approximately 2.0 to 2.5.
Inventors
- 👤 Andrew Joseph Woytek
- 👤 John Theodore Lileck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:11
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/082; C01B21/083; C01B21/0832; C01B21/0835
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
53 words
A process for preparing nitrogen trifluoride which comprises the step of contacting elemental fluorine in vapor phase with liquid phase ammonium acid fluoride maintained at a temperature of from about the melting temperature to a temperature not substantially above 400° F for a time sufficient to effect reaction and thereby form nitrogen trifluoride.
Claim 2
Dependent Claim
53 words
A process for preparing nitrogen trifluoride which comprises the step of contacting elemental fluorine in vapor phase with liquid phase ammonium acid fluoride maintained at a temperature of from about the melting temperature to a temperature not substantially above 400° F for a time sufficient to effect reaction and thereby form nitrogen trifluoride.
Claim 3
Dependent Claim
41 words
The process of claim 1 wherein said contacting of fluorine with said ammonium acid fluoride is effected by passing the fluorine through a sparger having a plurality of holes therein not substantially larger than about 0.5 inch 2 in cross-sectional area.
Claim 4
Dependent Claim
16 words
The process of claim 2 wherein ammonia is injected into the liquid phase ammonium acid fluoride.
Claim 5
Dependent Claim
34 words
The process of claim 3 wherein a mole ratio of by-product hydrogen fluoride to ammonia of at least 2.0 is established and maintained while fluorine is passed through the liquid phase ammonium acid fluoride.
Claim 6
Dependent Claim
33 words
The process of claim 5 wherein ammonia is injected into the ammonium acid fluoride in a proportion sufficient to maintain a mole ratio of hydrogen fluoride to ammonia of about 2:0 to 2:5.
Claim 7
Dependent Claim
44 words
The process of claim 5 wherein said fluorine is charged to the ammonium acid fluoride at a rate of from about 2 to about 20 standard curbic feet per hour per square foot of cross-sectional area of said liquid phase ammonium acid fluoride bath.
Claim 8
Dependent Claim
36 words
The process of claim 6 wherein said ammonium acid fluoride is maintained at a temperature of from about 260° to 320° F, and the pressure in said fluorination is from about atmospheric to about 50 psig.
Claim 9
Dependent Claim
39 words
The process of claim 7 wherein said fluorine is passed through a sparger and then through a packed column having a diameter of from about 11/2-3 inches, and a height of about 6-18 inches vertically disposed in said reactor.
References Cited (Backward Citations)
SU196734A1
Cited
US3961024A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-22 | 1981-11-21 | 1982-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-22 | 1985-11-21 | 1986-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-22 | 1989-11-21 | 1990-05-23 | $7700.00 | Window Closed / Lapsed |