Patent US2549549A successfully refreshed from Google Patents.
US2549549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing aluminum trihydrate
Assignee: Alcoa Corp
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Filing: 1947-06-07
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Granted: 1951-04-17
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Expires: 1967-06-07
Abstract
No abstract record available.
Inventors
- 👤 James R Wall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:37
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/02; C01F7/04; C01F7/14; C01F7/144
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
122 words
THE PROCESS FOR PRODUCING CRYSTALLINE ALUMINUM TRIHYDRATE FROM A SODIUM ALUMINATE SOLUTION, COMPRISING THE STEPS OF PRECIPITATING ARMORPHOUS ALUMINUM HYDROXIDE FROM A SOLUTION OF AN ALUMINUM SALT, MAINTAINING THE SAID PRECIPITATE IN UNDISSOLVED FORM IN CONTACT WITH A SOLUTION OF AN ALKALI METAL COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE CARBONATES AND HYDROXIDES FOR SUFFICIENT TIME TO CONVERT ONLY PART OF THE SAID AMORPHOUS ALUMINUM HYDROXIDE TO CRYSTALLINE ALUMINUM TRUHYDRATE AND THUS PRODUCE A MIXTURE OF AMORPHOUS ALUMINUM HYDROXIDE AND MINUTE PARTICLES OF CRYSTALLINE ALUMINUM TRIHYDRATE, THEREAFTER ADDING THE SAID MIXTURE OF AMORPHOUS ALUMINUM HYDROXIDE AND ALUMINUM TRIHYDRATE TO THE SAID SODIUM ALUMINATE SOLUTION AND AGITATING THE RESULTANT MIX, WHEREBY ALUMINUM TRIHYDRATE IS PRECIPITATED FROM THE SODIUM ALUMINATE SOLUTION BY AUTO-PRECIPITATION.
Claim 2
Dependent Claim
122 words
THE PROCESS FOR PRODUCING CRYSTALLINE ALUMINUM TRIHYDRATE FROM A SODIUM ALUMINATE SOLUTION, COMPRISING THE STEPS OF PRECIPITATING ARMORPHOUS ALUMINUM HYDROXIDE FROM A SOLUTION OF AN ALUMINUM SALT, MAINTAINING THE SAID PRECIPITATE IN UNDISSOLVED FORM IN CONTACT WITH A SOLUTION OF AN ALKALI METAL COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE CARBONATES AND HYDROXIDES FOR SUFFICIENT TIME TO CONVERT ONLY PART OF THE SAID AMORPHOUS ALUMINUM HYDROXIDE TO CRYSTALLINE ALUMINUM TRUHYDRATE AND THUS PRODUCE A MIXTURE OF AMORPHOUS ALUMINUM HYDROXIDE AND MINUTE PARTICLES OF CRYSTALLINE ALUMINUM TRIHYDRATE, THEREAFTER ADDING THE SAID MIXTURE OF AMORPHOUS ALUMINUM HYDROXIDE AND ALUMINUM TRIHYDRATE TO THE SAID SODIUM ALUMINATE SOLUTION AND AGITATING THE RESULTANT MIX, WHEREBY ALUMINUM TRIHYDRATE IS PRECIPITATED FROM THE SODIUM ALUMINATE SOLUTION BY AUTO-PRECIPITATION.
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) | 1954-04-16 | 1954-10-16 | 1955-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-04-16 | 1958-10-16 | 1959-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-04-16 | 1962-10-16 | 1963-04-17 | $7700.00 | Window Closed / Lapsed |