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US2549549A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing aluminum trihydrate

Assignee: Alcoa Corp
•
Filing: 1947-06-07
•
Granted: 1951-04-17
•
Expires: 1967-06-07
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Abstract

No abstract record available.

Inventors

  • 👤 James R Wall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 12:40
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)

US1835271A Cited
US2247624A Cited
US2406420A Cited

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

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