US2655430A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making calcium sulfate from refinery waste acid
Assignee: Shell Development Co
•
Filing: 1948-05-18
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Granted: 1953-10-13
•
Expires: 1968-05-18
Abstract
No abstract record available.
Inventors
- 👤 Knapel F Schiermeier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:30
CPC Classifications
C; C01; C01F; C01F11/00; C01F11/46
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
IN A METHOD OF MAKING CALCIUM SULFATE FROM REFINERY WASTE SULFURIC ACID CONTAINING PETROLEUM CONTAMINANTS THE STEPS OF MIXING SAID ACID WITH LIME APPROXIMATELY IN THE PROPORTION TO NEUTRALIZE THE AVAILABLE SULFURIC ACID, AND REMOVING SUBSTANTIALLY ALL OF SAID CONTAMINANTS BY CALCINING THE RESULTING MIXTURE AT A TEMPERATURE ABOVE ABOUT 900* F. IN AN OXYGEN-CONTAINING GAS AND THEREBY BURNING SAID CONTAMINANTS TO PRODUCE A CALCIUM SULFATE PRODUCT SUBSTANTIALLY FREE FROM CARBON AND HYDROCARBON MATERIAL.
Claim 2
Dependent Claim
74 words
IN A METHOD OF MAKING CALCIUM SULFATE FROM REFINERY WASTE SULFURIC ACID CONTAINING PETROLEUM CONTAMINANTS THE STEPS OF MIXING SAID ACID WITH LIME APPROXIMATELY IN THE PROPORTION TO NEUTRALIZE THE AVAILABLE SULFURIC ACID, AND REMOVING SUBSTANTIALLY ALL OF SAID CONTAMINANTS BY CALCINING THE RESULTING MIXTURE AT A TEMPERATURE ABOVE ABOUT 900* F. IN AN OXYGEN-CONTAINING GAS AND THEREBY BURNING SAID CONTAMINANTS TO PRODUCE A CALCIUM SULFATE PRODUCT SUBSTANTIALLY FREE FROM CARBON AND HYDROCARBON MATERIAL.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-10-12 | 1957-04-13 | 1957-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-10-12 | 1961-04-13 | 1961-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-10-12 | 1965-04-13 | 1965-10-13 | $7700.00 | Window Closed / Lapsed |