Patent US4193853A successfully refreshed from Google Patents.
US4193853A
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US
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Decontaminating metal surfaces
Assignee: United States Department of Energy
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Filing: 1979-05-15
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Granted: 1980-03-18
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Expires: 1999-05-15
Abstract
Abstract This invention relates to an electrolyte and an electrolytic method for removing radioactive contaminants from the surface of a metallic substrate.
Inventors
- 👤 Everett L. Childs
- 👤 Jack L. Long
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:08
CPC Classifications
C; C25; C25F; C25F3/00; C25F3/02; G; G21; G21F; G21F9/00; G21F9/001; G21F9/002; G21F9/004
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
47 words
A process for decontaminating an object having a surface contaminated with a radioactive substance comprising: contacting said object with a basic aqueous solution containing nitrate, fluoride, borate, and oxalate anions; thereafter electrolytically removing a surface layer of said object; and subsequently separating resulting precipitate from said solution.
Claim 2
Dependent Claim
47 words
A process for decontaminating an object having a surface contaminated with a radioactive substance comprising: contacting said object with a basic aqueous solution containing nitrate, fluoride, borate, and oxalate anions; thereafter electrolytically removing a surface layer of said object; and subsequently separating resulting precipitate from said solution.
Claim 3
Dependent Claim
15 words
The process of claim 1 further comprising reusing said solution after said separating said precipitate.
Claim 4
Dependent Claim
61 words
The process of claim 1 wherein the basic aqueous solution comprises from 50 to 500 g/1 NaNO 3 , from 0.1 to 2.5 g/1 NaF, from 1 to 20 g/1 Na 2 B 4 0 7 ·1OH 2 O, and from 0.1 to 4 g/1 Na 2 C 2 O 4 ; said solution having a pH from 7 to 11.
Claim 5
Dependent Claim
50 words
The process of claim 2 wherein the basic aqueous solution comprises about 200 g/1 NaNO 3 about 2 g/1 NaF, about 20 g/1 Na 2 B 4 O 7 ·1OH 2 , and about 2 g/1 Na 2 C 2 O 4 ; said solution having a pH about 9.
Claim 6
Dependent Claim
40 words
The process of claim 1 wherein said electrolysis is conducted with a potential of from 4 to 24 volts, a current density of from 1 to 8 amps/in 2 , and at a temperature of from 25° to 90° C.
Claim 7
Dependent Claim
33 words
The process of claim 1 wherein the object is of an alloy including at least one of the metals iron, chromium, nickel, aluminum, copper, or lead and the radioactive substance is an actinide.
Claim 8
Dependent Claim
20 words
The process of claim 1 wherein the metal object is stainless steel and the radioactive substances is plutonium or americium.
Claim 9
Dependent Claim
49 words
A basic aqueous solution for electrochemical machining comprising from 50 to 500 g/1 NaNO 3 , from 0.1 to 2.5 g/1 NaF, from 1 to 20 g/l Na 2 B 4 O 7 ·1OH 2 O, and from 0.1 to 4 g/1 Na 2 C 2 O 4 .
Claim 10
Dependent Claim
49 words
A basic aqueous solution for electrochemical machining comprising from 50 to 500 g/1 NaNO 3 , from 0.1 to 2.5 g/1 NaF, from 1 to 20 g/l Na 2 B 4 O 7 ·1OH 2 O, and from 0.1 to 4 g/1 Na 2 C 2 O 4 .
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) | 1983-03-18 | 1983-09-17 | 1984-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-18 | 1987-09-17 | 1988-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-18 | 1991-09-17 | 1992-03-18 | $7700.00 | Window Closed / Lapsed |