Patent US2888494A successfully refreshed from Google Patents.
US2888494A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of trichloroethylene
Assignee: Columbia Southern Chemical Corp
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Filing: 1954-10-21
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Granted: 1959-05-26
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Expires: 1974-10-21
Abstract
No abstract record available.
Inventors
- 👤 Lehr F Kissling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:14
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/38
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
107 words
THE METHOD WHICH COMPRISES SEQUENTIALLY PASSING ACIDIC TRICHLOROETHYLENE CONTAINING ACIDITY NOT MATERIALLY AFFECTED BY TREATMENT WITH AQUEOUS ALKALINE MATERIALS THROUGH A LIQUID PERMEABLE DRIED BED OF SYNTHETIC, ORGANIC ANIONIC ION-EXCHANGE RESIN WHEREBY TO REDUCE SAID ACIDITY AND CONTENTS OF ACIDUOUS MATERIALS NOT AFFECTED BY TREATMENT WITH AQUEOUS ALKALINE MATERIAL, DISCONTINUING THE PASSAGE OF TRICHLOROETHYLENE WHEN THE ACTIVITY OF THE RESIN BED DIMINISHES, REGENERATING THE RESIN BED BY CONTACTING ATED BED TO REMOVE MOISTURE AND TO ESTABLISH A BED ATED BED TO REMOVE MOISTURE AND TO ESTABLISH A BED CONTAINING LESS THAN 20 PERCENT WATER BY WEIGHT, AND THEREAFTER RESUMING THE PASSAGE OF ACIDIC TRICHLOROETHYLENE THROUGHT THE BED.
Claim 2
Independent Claim
107 words
THE METHOD WHICH COMPRISES SEQUENTIALLY PASSING ACIDIC TRICHLOROETHYLENE CONTAINING ACIDITY NOT MATERIALLY AFFECTED BY TREATMENT WITH AQUEOUS ALKALINE MATERIALS THROUGH A LIQUID PERMEABLE DRIED BED OF SYNTHETIC, ORGANIC ANIONIC ION-EXCHANGE RESIN WHEREBY TO REDUCE SAID ACIDITY AND CONTENTS OF ACIDUOUS MATERIALS NOT AFFECTED BY TREATMENT WITH AQUEOUS ALKALINE MATERIAL, DISCONTINUING THE PASSAGE OF TRICHLOROETHYLENE WHEN THE ACTIVITY OF THE RESIN BED DIMINISHES, REGENERATING THE RESIN BED BY CONTACTING ATED BED TO REMOVE MOISTURE AND TO ESTABLISH A BED ATED BED TO REMOVE MOISTURE AND TO ESTABLISH A BED CONTAINING LESS THAN 20 PERCENT WATER BY WEIGHT, AND THEREAFTER RESUMING THE PASSAGE OF ACIDIC TRICHLOROETHYLENE THROUGHT THE BED.
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) | 1962-05-25 | 1962-11-24 | 1963-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-05-25 | 1966-11-24 | 1967-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-05-25 | 1970-11-24 | 1971-05-26 | $7700.00 | Window Closed / Lapsed |