Patent US4340499A successfully refreshed from Google Patents.
US4340499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for treating radioactive solutions
Assignee: Kraftwerk Union AG
•
Filing: 1980-02-28
•
Granted: 1982-07-20
•
Expires: 2000-02-28
Abstract
Abstract Concentrated liquid waste solutions containing radioactive substances and also complex formers is treated by maintaining pH 5 and adding KMnO 4 to oxidize complex formers, and solidifying and embedding the resultant solution in a binder. Dilute solutions are also maintained at a pH of 5 and excess KMnO 4 added. The excess MnO 4 - is reduced to MnO 2 by addition MnSO 4 . MnO 2 separates and adsorbs radionuclides Mn-54, Sb-124, Sb-125 and 65-Zn contained in the solution.
Inventors
- 👤 Gustav Fischer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:59
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/16; G21F9/162; G21F9/165; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/911; Y10S210/912
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
208 words
Method of treating aqueous waste solutions containing Co 58 and Co 60 , other radionuclides selected from the group consisting of Mn 54 , Sb 124 , Sb 125 and Zn 65 and mixtures thereof and organic complexing agents, which comprises maintaining the pH of the solution at about 5 and adding alkali-metal permanganate to the solution in excess amount to oxidize the complexing agents and subsequently adding MnSO 4 to the solution to reduce the excess MnO 4 - in the solution to MnO 2 which latter separates as a solid from the solution and adsorbs said other radionuclides contained in the aqueous solution subjected to treatment, separating the solids from the solution raising the pH of the separated solution to about 10.5, adding a complex [Co +3 (NH 3 ) 6 ] Cl 3 salt as a carrier for Co 58 and Co 60 to the solution, adding a reducing agent to the solution to reduce Co +3 to Co +2 , adding a decomplexing agent to free Co +2 from the complex, and then adding a precipitating agent to the solution to precipitate Co +2 as a compound insoluble in the solution, and subsequently encapsulating the said solids and said insoluble compounds in a binder.
Claim 2
Dependent Claim
208 words
Method of treating aqueous waste solutions containing Co 58 and Co 60 , other radionuclides selected from the group consisting of Mn 54 , Sb 124 , Sb 125 and Zn 65 and mixtures thereof and organic complexing agents, which comprises maintaining the pH of the solution at about 5 and adding alkali-metal permanganate to the solution in excess amount to oxidize the complexing agents and subsequently adding MnSO 4 to the solution to reduce the excess MnO 4 - in the solution to MnO 2 which latter separates as a solid from the solution and adsorbs said other radionuclides contained in the aqueous solution subjected to treatment, separating the solids from the solution raising the pH of the separated solution to about 10.5, adding a complex [Co +3 (NH 3 ) 6 ] Cl 3 salt as a carrier for Co 58 and Co 60 to the solution, adding a reducing agent to the solution to reduce Co +3 to Co +2 , adding a decomplexing agent to free Co +2 from the complex, and then adding a precipitating agent to the solution to precipitate Co +2 as a compound insoluble in the solution, and subsequently encapsulating the said solids and said insoluble compounds in a binder.
Claim 3
Dependent Claim
62 words
Method according to claim 1, wherein the reducing agent is a compound selected from the group consisting of Na 2 S 2 O 4 , FeSO 4 and SnCl 2 , wherein the decomplexing agent is a compound containing an atom selected from the group consisting of Ca +2 and Sr +2 , and wherein the precipitating agent is NH 4 HS.
Claim 4
Dependent Claim
22 words
Method according to claim 1 or claim 2, wherein the oxidizing of the complexing agents is continued for at least 10 hours.
References Cited (Backward Citations)
US2769780A
Cited
US3013978A
Cited
US3272738A
Cited
DE1517664A1
Cited
FR1520681A
Cited
US3873362A
Cited
JPS5185266A
Cited
US4226640A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-07-19 | 1986-01-18 | 1986-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-19 | 1990-01-18 | 1990-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-19 | 1994-01-18 | 1994-07-20 | $7700.00 | Window Closed / Lapsed |