Patent US4474663A successfully refreshed from Google Patents.
US4474663A
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Method of regenerating gels for use in liquid chromatography
Assignee: Japan Exlan Co Ltd
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Filing: 1983-01-26
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Granted: 1984-10-02
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Expires: 2003-01-26
Abstract
Abstract This invention provides an industrially advantageous method of regenerating a large quantity of contaminated gels by treating a contaminated gel which has become less active in separation performance with an aqueous solution of a metallic salt or ammonium salt of thiocyanic acid, nitric acid, or hydrogen iodide having a concentration of from 30 weight % to saturation, at a temperature between 50° and 120° C., thereby effectively removing contaminants in the interstices among the gel particles or contaminants on the active points.
Inventors
- 👤 Shigeru Nakajima
- 👤 Masahiko Ozaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:25
CPC Classifications
B; B01; B01D; B01D15/00; B01D15/08; B01J; B01J20/00; B01J20/281; B01J20/291; B01D15/10; B01D15/20; B01D15/203; B01J20/22; B01J20/26; B01J20/265; B01J20/267; B01J20/30; B01J20/34; B01J20/3425; B01J20/345; B01J20/3475; B01D15/26; B01D15/34; B01J2220/00; B01J2220/50; B01J2220/54
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
71 words
A method of regenerating gels for use in liquid chromatography, characterized in that a gel which has become less active in separation performance is treated with an aqueous solution of a metallic salt or ammonium salt or a member selected from the group consisting of a salt of thiocyanic acid or hydrogen iodide having a concentration of from 30 weight % to saturation, at a temperature between 50° and 120° C.
Claim 2
Independent Claim
71 words
A method of regenerating gels for use in liquid chromatography, characterized in that a gel which has become less active in separation performance is treated with an aqueous solution of a metallic salt or ammonium salt or a member selected from the group consisting of a salt of thiocyanic acid or hydrogen iodide having a concentration of from 30 weight % to saturation, at a temperature between 50° and 120° C.
Claim 3
Dependent Claim
23 words
The method as claimed in claim 1 wherein said gel is treated with an alkali-metal salt or the ammonium salt of thiocyanic acid.
Claim 4
Dependent Claim
21 words
The method as claimed in claim 1 wherein said gel is treated batchwise under vibration or stirring in a treating bath.
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) | 1987-10-02 | 1988-04-02 | 1988-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-02 | 1992-04-02 | 1992-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-02 | 1996-04-02 | 1996-10-02 | $7700.00 | Window Closed / Lapsed |