Patent US2669713A successfully refreshed from Google Patents.
US2669713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of regenerating anion exchange resins
Assignee: Dow Chemical Co
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Filing: 1950-10-27
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Granted: 1954-02-16
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Expires: 1970-10-27
Abstract
No abstract record available.
Inventors
- 👤 Roy H Osmun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:56
CPC Classifications
B; B01; B01J; B01J49/00; B01J49/50; B01J49/57
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
128 words
IN A PROCESS WHICH COMPRISES REMOVING DISSOLVED SILICA FROM AN AQUEOUS SOLUTION BY CONTACTING THE SOLUTION WITH A STRONGLY BASIC ANION EXCHANGE RESIN CONTAINING QUARTERNARY AMMONIUM HYDROXIDE GROUPS, WHICH ANION EXCHANGE RESIN IS COMPOSED OF THE REACTION PRODUCT OF A HALOMETHYLATED BENZENE-INSOLUBLE COPOLYMER OF A MONOVINYL AROMATIC HYDROCARBON AND A DIVINYL AROMATIC HYDROCARBON WITH A TERTIARY AMINE, WHEREBY THE DISSOLVED SILICA IS ABSORBED ON THE ANION EXCHANGE RESIN, THE STEP WHICH CONSISTS IN THEREAFTER CONTACTING THE ANION EXCHANGE RESIN WITH AN AQUEOUS SOLUTION OF AN ALKALI METAL HYDROXIDE IN CONCENTRATION OF FROM ONE TO FOUR PER CENT BY WEIGHT AT A TEMPERATURE OF FROM 90* TO 120* F. WHEREBY THE ABSORBED SILICA IS DISPLACED FROM THE ANION EXCHANGE RESIN AND SAID RESIN IS REGENERATED TO ITS HYDROXIDE FORM.
Claim 2
Dependent Claim
128 words
IN A PROCESS WHICH COMPRISES REMOVING DISSOLVED SILICA FROM AN AQUEOUS SOLUTION BY CONTACTING THE SOLUTION WITH A STRONGLY BASIC ANION EXCHANGE RESIN CONTAINING QUARTERNARY AMMONIUM HYDROXIDE GROUPS, WHICH ANION EXCHANGE RESIN IS COMPOSED OF THE REACTION PRODUCT OF A HALOMETHYLATED BENZENE-INSOLUBLE COPOLYMER OF A MONOVINYL AROMATIC HYDROCARBON AND A DIVINYL AROMATIC HYDROCARBON WITH A TERTIARY AMINE, WHEREBY THE DISSOLVED SILICA IS ABSORBED ON THE ANION EXCHANGE RESIN, THE STEP WHICH CONSISTS IN THEREAFTER CONTACTING THE ANION EXCHANGE RESIN WITH AN AQUEOUS SOLUTION OF AN ALKALI METAL HYDROXIDE IN CONCENTRATION OF FROM ONE TO FOUR PER CENT BY WEIGHT AT A TEMPERATURE OF FROM 90* TO 120* F. WHEREBY THE ABSORBED SILICA IS DISPLACED FROM THE ANION EXCHANGE RESIN AND SAID RESIN IS REGENERATED TO ITS HYDROXIDE FORM.
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) | 1957-02-15 | 1957-08-17 | 1958-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-15 | 1961-08-17 | 1962-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-15 | 1965-08-17 | 1966-02-16 | $7700.00 | Window Closed / Lapsed |