US3852407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing alkyl iodides from air by mercuric nitrate solution
Assignee: United States Atomic Energy Commission
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Filing: 1972-08-08
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Granted: 1974-12-03
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Expires: 1992-08-08
Abstract
Abstract An improved process for contacting and removing iodine and particularly alkyl iodides from an air stream comprising the use of a relatively concentrated nitric acid solution comprising mercuric ions recycled through a gas contactor. Concurrently, a minor fraction of the solution is passed through an evaporator to oxidize and concentrate the accumulated iodine causing it to precipitate as mercuric iodate, thereby allowing essentially complete recycle of the mercury and nitric acid.
Inventors
- 👤 J Schmitt
- 👤 D Crouse
- 👤 W Howerton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:39
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/68; B01D53/70
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
54 words
A METHOD FOR REMOVING ALKYL IODIDES FROM AN AIR STREAM COMPRISING THE STEPS OF CONTACTING SAID AIR STREAM WITH AN AQUEOUS SOLUTION OF NITRIC ACID AT A CONCENTRATION OF FROM 66 TP 14 MOLAR CONTAINING MERCURIC NITRATE AT A CONCENTRATION OF AT LEAST 0.1 MOLAR, AT A TEMPERATURE OF FROM 25* TO 80*C, THUS
Claim 2
Independent Claim
54 words
A METHOD FOR REMOVING ALKYL IODIDES FROM AN AIR STREAM COMPRISING THE STEPS OF CONTACTING SAID AIR STREAM WITH AN AQUEOUS SOLUTION OF NITRIC ACID AT A CONCENTRATION OF FROM 66 TP 14 MOLAR CONTAINING MERCURIC NITRATE AT A CONCENTRATION OF AT LEAST 0.1 MOLAR, AT A TEMPERATURE OF FROM 25* TO 80*C, THUS
Claim 3
Dependent Claim
87 words
The method according to claim 1 wherein said solution contacts said air stream countercurrently in a packed vertical column and comprising the steps of dividing effluent from said column into a first part and a second part, evaporating said first part to precipitate said sorbed iodide as mercuric iodate, said step of evaporating giving off fumes of nitric acid, condensing said fumes to form a nitric acid condensate, combining said condensate with said effluent prior to dividing said effluent, and reintroducing said second part inTo said column.
Claim 4
Dependent Claim
55 words
The method according to claim 2 wherein said air stream passes from said column to a secondary column for further decontamination, and comprising contacting said air stream in said secondary column with a secondary aqueous solution of nitric acid and mercuric nitrate at molarity concentrations of about 0.1 to 1 and 0.005 to 0.02, respectively.
Claim 5
Dependent Claim
25 words
The method according to claim 3 wherein said secondary solution further comprises nonradioactive iodine at a concentration of 5 to 50 mg/liter for isotopic dilution.
Claim 6
Dependent Claim
105 words
The method according to claim 1 wherein said step of contacting is carried out countercurrently in a column and further comprising the steps of boiling effluent solution from said column under reflux conditions to convert said sorbed iodides to mercuric iodate, thus forming a refluxed solution, dividing said refluxed solution into a first part and a second part, boiling said first part to precipitate mercuric iodate and to give off nitric acid fumes, condensing said nitric acid fumes thus forming a nitric acid condensate, adding said condensate to said effluent solution prior to dividing said effluent solution and recycling said second part to said column.
Claim 7
Dependent Claim
26 words
The method according to claim 1 wherein said nitric acid concentration is 8 to 10 molar and said mercuric nitrate concentration is 0.1 to 0.6 molar.
Claim 8
Dependent Claim
16 words
The method according to claim 6 wherein said mercuric nitrate concentration is 0.2 to 0.4 molar.
Claim 9
Dependent Claim
25 words
The method according to claim 1 wherein said solution has a volume flow rate of 0.3 to 2 percent of the air volume flow rate.
Claim 10
Dependent Claim
21 words
The method according to claim 2 wherein said first part is 1 to 15 percent of the volume of said effluent.
References Cited (Backward Citations)
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US3466137A
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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) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |