US3699209A
Expired / Lapsed
US
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Hf removal system
Assignee: Universal Oil Products Co
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Filing: 1971-02-26
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Granted: 1972-10-17
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Expires: 1991-02-26
Abstract
Abstract In scrubbing systems wherein HF contained in gaseous steams is removed by scrubbing with an aqueous calcium hydroxide system, corrosion is diminished by the addition of up to about 3 percent by weight of an alkali metal hydroxide.
Inventors
- 👤 Dennis J Ward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:01
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/14833; C07C7/1485; B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/68
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
16 words
The improvement of claim 1 wherein said scrubbing medium comprises an aqueous suspension of calcium hydroxide.
Claim 2
Dependent Claim
13 words
The improvement of claim 1 wherein said alkali metal hydroxide is potassium hydroxide.
Claim 3
Dependent Claim
13 words
The improvement of claim 1 wherein said alkali metal hydroxide is sodium hydroxide.
Claim 4
Dependent Claim
21 words
The improvement of claim 1 wherein said scrubbing medium contains about 0.5 to about 1 percent, by weight, alkali metal hydroxide.
Claim 5
Dependent Claim
11 words
The improvement of claim 5 wherein said hydroxide is potassium hydroxide.
Claim 6
Dependent Claim
11 words
The improvement of claim 5 wherein said hydroxide is sodium hydroxide.
Claim 7
Dependent Claim
24 words
The improvement of claim 1 wherein said hydrogen fluoride containing gaseous stream comprises a relief gas stream from a hydrogen fluoride catalyzed alkylation unit.
Claim 8
Dependent Claim
13 words
The improvement of claim 8 wherein said hydrogen fluoride stream contains light hydrocarbons.
Claim 9
Dependent Claim
20 words
The improvement of claim 8 wherein said hydrogen fluoride stream comprises hydrogen fluoride in admixture with an inert gas carrier.
References Cited (Backward Citations)
US2686151A
Cited
US2813000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |