Patent US2993757A successfully refreshed from Google Patents.
US2993757A
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Process for recovering acid values from mixed acid waste
Assignee: Crucible Steel Company of America
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Filing: 1958-07-07
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Granted: 1961-07-25
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Expires: 1978-07-07
Abstract
No abstract record available.
Inventors
- 👤 John O Dasher
- 👤 Goldstein David
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:23
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/36; C01; C01B; C01B21/00; C01B21/20; C01B21/38; C01B21/46; C01B7/00; C01B7/09; C01B7/13; Y; Y10; Y10S; Y10S159/00; Y10S159/19; Y10S423/00; Y10S423/01; Y10S423/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
131 words
IN THE METHOD OF RECOVERING NITRIC AND HYDROFLUORIC ACID VALUES FROM A WASTE PICKLE LIQUOR SOLUTION CONTAINING NITRATES AND FLUORIDES IN SOLUTION, THE STEPS OF: DISTILLING THE WASTE PICKLE LIQUOR SOLUTION AT ABOUT 150*F. AND THREE INCHES OF MERCURY TO DRIVE OFF A MAXIMUM OF WATER WITHOUT SUBSTANTIAL LOSS OF ACID RADICAL, ADDING SULFURIC ACID TO THE CONCENTRATED LIQUOR FROM SAID DISTILLATION STEP, FURTHER DISTILLING THE MIXED PRODUCTY AT 150*F. AND ONE INCH OF MERCURY TO DRIVE OFF NITRIC AND HYDROFLUORIC ACID WHILE FORMING A 25% SOLIDS SLURRY OF SULFATE SALTS IN SULFURIC ACID, SEPARATING THE SULFATE SALTS FROM THE SULFURIC ACID SLURRY, SEPARATING THE SULFATE SALTS FROM THE SULTHE SEPERATION STEP THROUGH SAID LAST TYPE MENTIONED DISTILLATION PROCESS, AND CONDENSING THE VAPORS DERIVED FROM THE FIRST AND SECOND DISTILLATION STEPS.
Claim 2
Dependent Claim
131 words
IN THE METHOD OF RECOVERING NITRIC AND HYDROFLUORIC ACID VALUES FROM A WASTE PICKLE LIQUOR SOLUTION CONTAINING NITRATES AND FLUORIDES IN SOLUTION, THE STEPS OF: DISTILLING THE WASTE PICKLE LIQUOR SOLUTION AT ABOUT 150*F. AND THREE INCHES OF MERCURY TO DRIVE OFF A MAXIMUM OF WATER WITHOUT SUBSTANTIAL LOSS OF ACID RADICAL, ADDING SULFURIC ACID TO THE CONCENTRATED LIQUOR FROM SAID DISTILLATION STEP, FURTHER DISTILLING THE MIXED PRODUCTY AT 150*F. AND ONE INCH OF MERCURY TO DRIVE OFF NITRIC AND HYDROFLUORIC ACID WHILE FORMING A 25% SOLIDS SLURRY OF SULFATE SALTS IN SULFURIC ACID, SEPARATING THE SULFATE SALTS FROM THE SULFURIC ACID SLURRY, SEPARATING THE SULFATE SALTS FROM THE SULTHE SEPERATION STEP THROUGH SAID LAST TYPE MENTIONED DISTILLATION PROCESS, AND CONDENSING THE VAPORS DERIVED FROM THE FIRST AND SECOND DISTILLATION STEPS.
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) | 1964-07-24 | 1965-01-23 | 1965-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-07-24 | 1969-01-23 | 1969-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-07-24 | 1973-01-23 | 1973-07-25 | $7700.00 | Window Closed / Lapsed |