US2794704A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of spent sulfuric acid
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1954-03-19
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Granted: 1957-06-04
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Expires: 1974-03-19
Abstract
No abstract record available.
Inventors
- 👤 Henry C Paulsen
- 👤 Joseph W Dowling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:31
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/69; C01B17/90; C01B17/92; C01B17/925
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
139 words
THE PROCESS OF PURIFYING SPENT AQUEOUS SULFURIC ACID OF 40 TO 60 WEIGHT PERCENT H2O4 CONTAINING RELATIVELY SMALL AMOUNTS OF CARBONACEOUS IMPURITIES, WHICH COMPRISES FIRST TREATING SAID SPENT ACID WITH AN ADMIXED PHENOLIC SOLVENT FOR SOLUBLE CARBONACEOUS TARS AND RESINS AMONG SAID IMPURITIES, SEPARATING THE THUS TREATED AQUEOUS ACID FROM SAID SOLVENT AND FROM IMPURITIES EXTRACTED BY THE SOLVENT, SUBSEQUENTLY HEATING THE AQUEOUS ACID SEPARATED FROM SAID SOLVENT AND EXTRACTED IMPURITIES TO AN ELEVATED TEMPERATURE IN THE RANGE OF 230*F. TO 285*F. FOR A PERIOD OF 5 TO 30 MINUTES, DURING SAID HEATING REMOVING ORGANIC IMPURITIES WHICH ARE BOILED FROM THE AQUEOUS ACID, THEN FILTERING THE ACID AFTER SAID HEATING BY CONTACT WITH THE SOLID ADSORBENT MATERIAL AT A TEMPERATURE IN THE RANGE OF 50 TO 180*F. IN ORDER TO REMOVE REMAINING IMPURITIES WHICH REMAIN UNVOLATILIZED IN THE ACID.
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) | 1960-06-03 | 1960-12-03 | 1961-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-06-03 | 1964-12-03 | 1965-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-06-03 | 1968-12-03 | 1969-06-04 | $7700.00 | Window Closed / Lapsed |