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US4340499A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for treating radioactive solutions

Assignee: Kraftwerk Union AG
•
Filing: 1980-02-28
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Granted: 1982-07-20
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Expires: 2000-02-28
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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 11:47
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

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