Patent US4808318A successfully refreshed from Google Patents.
US4808318A
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Process for cesium decontamination and immobilization
Assignee: United States Department of Energy
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Filing: 1988-04-25
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Granted: 1989-02-28
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Expires: 2008-04-25
Abstract
Abstract Cesium can be selectively recovered from a nuclear waste solution containing cesium together with other metal ions by contact with a modified phlogopite which is a hydrated, sodium phlogopite mica. Once the cesium has entered the modified phlogopite it is fixed and can be safely stored for long periods of time.
Inventors
- 👤 Sridhar Komarneni
- 👤 Rustum Roy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:32
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/12
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
64 words
A process for separating and recovering cesium ions from a feed solution comprising: contacting the feed solution containing cesium together with other metal ions with a modified phlogopite which is a hydrated, sodium phlogopite mica whereby the cesium ions are selectively taken up by the modified phlogopite, and separating the phlogopite containing the cesium ions from the feed solution, thereby recovering the cesium ions.
Claim 2
Dependent Claim
64 words
A process for separating and recovering cesium ions from a feed solution comprising: contacting the feed solution containing cesium together with other metal ions with a modified phlogopite which is a hydrated, sodium phlogopite mica whereby the cesium ions are selectively taken up by the modified phlogopite, and separating the phlogopite containing the cesium ions from the feed solution, thereby recovering the cesium ions.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein the feed solution also contains sodium and calcium ions.
Claim 4
Dependent Claim
17 words
The process of claim 2 wherein the modified phlogopite mica has a c-axis spacing of about 12.23Å.
Claim 5
Independent Claim
75 words
A method of recovering and fixing radioactive cesium ions contained in a liquid waste feed solution for long-term storage comprising: contacting the liquid waste with a modified phlogopite which is a hydrated sodium phlogopite mica having a c-axis spacing of about 12.23Å whereby the cesium ions are selectively taken up by the modified phlogopite, and reducing the c-axis spacing an amount sufficient to lock-in the cesium ions, thereby immobilizing the cesium ions for long-term storage.
Claim 6
Independent Claim
75 words
A method of recovering and fixing radioactive cesium ions contained in a liquid waste feed solution for long-term storage comprising: contacting the liquid waste with a modified phlogopite which is a hydrated sodium phlogopite mica having a c-axis spacing of about 12.23Å whereby the cesium ions are selectively taken up by the modified phlogopite, and reducing the c-axis spacing an amount sufficient to lock-in the cesium ions, thereby immobilizing the cesium ions for long-term storage.
Claim 7
Dependent Claim
21 words
The method of claim 4 wherein sufficient cesium ions are taken up by the modified phlogopite to reduce the c-axis spacing.
Claim 8
Dependent Claim
26 words
The method of claim 4 wherein the cesium-containing phlogopite is heated to about 150° C. for a period of time sufficient to reduce the c-axis spacing.
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) | 1992-02-28 | 1992-08-29 | 1993-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-28 | 1996-08-29 | 1997-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-28 | 2000-08-29 | 2001-02-28 | $7700.00 | Window Closed / Lapsed |