US4156646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of plutonium and americium from alkaline waste solutions
Assignee: United States Department of Energy
•
Filing: 1978-06-16
•
Granted: 1979-05-29
•
Expires: 1998-06-16
Abstract
Abstract High salt content, alkaline waste solutions containing plutonium and americium are contacted with a sodium titanate compound to effect removal of the plutonium and americium from the alkaline waste solution onto the sodium titanate and provide an effluent having a radiation level of less than 10 nCi per gram alpha emitters.
Inventors
- 👤 Wallace W. Schulz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:30
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5236; G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/10; G21F9/12; C02F2101/00; C02F2101/006
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
142 words
In the decontamination of plutonium reclamation facility salt waste, wherein said salt waste is first contacted with sodium hydroxide to form a precipitate and a supernatant liquid containing greater than 10 nCi/g alpha radiation of americium-241 and plutonium, and wherein said precipitate is selected from the group consisting of calcium hydroxide, magnesium hydroxide and iron hydroxide, and wherein said precipitate further extracts from 80 to 90% of the plutonium and greater than 99.9% of the americium from the salt waste, the improvement consisting essentially of contacting the supernatant liquid from the metal precipitation step with sodium titanate powder to adsorb said plutonium and americium-241 upon said sodium titanate powder and remove said plutonium and americium-241 from said supernatant liquid of said metal precipitation step and yield a plutonium and americium free effluent containing less than 10 -3 nCi per liter alpha emitters.
Claim 2
Dependent Claim
142 words
In the decontamination of plutonium reclamation facility salt waste, wherein said salt waste is first contacted with sodium hydroxide to form a precipitate and a supernatant liquid containing greater than 10 nCi/g alpha radiation of americium-241 and plutonium, and wherein said precipitate is selected from the group consisting of calcium hydroxide, magnesium hydroxide and iron hydroxide, and wherein said precipitate further extracts from 80 to 90% of the plutonium and greater than 99.9% of the americium from the salt waste, the improvement consisting essentially of contacting the supernatant liquid from the metal precipitation step with sodium titanate powder to adsorb said plutonium and americium-241 upon said sodium titanate powder and remove said plutonium and americium-241 from said supernatant liquid of said metal precipitation step and yield a plutonium and americium free effluent containing less than 10 -3 nCi per liter alpha emitters.
Claim 3
Dependent Claim
22 words
The process of claim 1 wherein said sodium titanate is a powder of a size range from 40 mesh to 140 mesh.
Claim 4
Dependent Claim
145 words
A process for decontaminating plutonium reclamation facility salt waste comprising contacting said salt waste with sodium hydroxide to effect precipitation of ferric hydroxide, magnesium hydroxide, and calcium hydroxide, and to scavenge from 80 to 90% of the plutonium in said salt waste and greater than 99.9% americium-241 from said salt waste, said metal precipitation step also yielding a supernatant liquid containing greater than about 0.03 microcuries per liter of americium-241 and greater than about 5 microcuries per liter of plutonium, thereafter contacting said supernatant liquid with a sodium titanate powder of from 40 to 140 mesh U.S. Standard Sieve Size Series, to adsorb the plutonium and the americium-241 upon said sodium titanate powder, the effluent from said sodium titanate sorption step containing less than about 10 -3 to 0.004 microcuries per liter plutonium and less than about 0.0002 to 0.0016 microcuries per liter of americium-241.
Claim 5
Dependent Claim
145 words
A process for decontaminating plutonium reclamation facility salt waste comprising contacting said salt waste with sodium hydroxide to effect precipitation of ferric hydroxide, magnesium hydroxide, and calcium hydroxide, and to scavenge from 80 to 90% of the plutonium in said salt waste and greater than 99.9% americium-241 from said salt waste, said metal precipitation step also yielding a supernatant liquid containing greater than about 0.03 microcuries per liter of americium-241 and greater than about 5 microcuries per liter of plutonium, thereafter contacting said supernatant liquid with a sodium titanate powder of from 40 to 140 mesh U.S. Standard Sieve Size Series, to adsorb the plutonium and the americium-241 upon said sodium titanate powder, the effluent from said sodium titanate sorption step containing less than about 10 -3 to 0.004 microcuries per liter plutonium and less than about 0.0002 to 0.0016 microcuries per liter of americium-241.
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) | 1982-05-28 | 1982-11-27 | 1983-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-28 | 1986-11-27 | 1987-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-28 | 1990-11-27 | 1991-05-29 | $7700.00 | Window Closed / Lapsed |