Patent US3304153A successfully refreshed from Google Patents.
US3304153A
Expired / Lapsed
US
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Method of preparing magnesia spinel
Assignee: Alcan Research and Development Ltd
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Filing: 1965-11-12
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Granted: 1967-02-14
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Expires: 1985-11-12
Abstract
No abstract record available.
Inventors
- 👤 Bakker Wate Thewis
- 👤 Lindsay James Gordon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:33
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/42; C01; C01F; C01F7/00; C01F7/02; C01F7/16; C01F7/162; C04B35/12; C04B35/44
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
148 words
A METHOD OF PREPARING A MAGNESIA SPINEL WHICH COMPRISES PREPARING A HOMOGENEOUS ADMIXTURE CONSISTING ESSENTIALLY OF A FINELY-DIVIDED ALUMIN-CONTRIBUTING COMPONENT AND A FINELY-DIVIDED MAGNESIA-CONTRIBUTING COMPONENT, SAID ALUMINA-CONTRIBUTING COMPONENT AND SAID MAGNESIA-CONTRIBUTING COMPONENT BEING PRESENT IN SAID ADMIXTURE IN SUBSTANTIALLY STOICHIOMETRIC AMOUNTS, SAID ALUMINA-CONTRIBUTING COMPONENT BEING SELECTED FROM THE GROUP CONSISTING OF ALUMINA HYDRATE, LIGHTLY CALCINED ALUMINA AND ALPHA-ALUMINA, AND SAID MAGNESIA-CONTRIBUTING COMPONENT BEING SELECTED FROM THE GROUP CONSISTING OF MAGNESIUM HYDROXIDE, MAGNESIUM CARBONATE, BASIC MAGNESIUM CARBONATE AND LIGHTLY CALCINED MAGNESIUM OXIDE, SAID ADMIXTURE ADDITIONALLY CONTAINING A MINOR AMOUNT OF A FLUORINE-CONTAINING MATERIAL IN THE RANGE 0.2-4.0% BYWEIGHT, OXIDE BASIS, WHEN SAID ALUMINA-CONTRIBUTING COMPONENT IS SUBSTANTIALLY FREE OF ALPHA-ALUMINA, CALCINING SAID ADMIXTURE AT A TEMPERATURE IN THE RANGE FROM ABOUT 850*C. TO ABOUT 1250*C. AND RECOVERING THE RESULTING CALCINED REACTION PRODUCT CONSISTING CHIEFLY OF MAGNESIA SPINEL, SAID FLUORINE-CONTAINING MATERIAL BEING CAPABLE OF LIBERATING HYDROGEN FLUORIDE DURING THE CALCINING OPERATION.
Claim 2
Independent Claim
148 words
A METHOD OF PREPARING A MAGNESIA SPINEL WHICH COMPRISES PREPARING A HOMOGENEOUS ADMIXTURE CONSISTING ESSENTIALLY OF A FINELY-DIVIDED ALUMIN-CONTRIBUTING COMPONENT AND A FINELY-DIVIDED MAGNESIA-CONTRIBUTING COMPONENT, SAID ALUMINA-CONTRIBUTING COMPONENT AND SAID MAGNESIA-CONTRIBUTING COMPONENT BEING PRESENT IN SAID ADMIXTURE IN SUBSTANTIALLY STOICHIOMETRIC AMOUNTS, SAID ALUMINA-CONTRIBUTING COMPONENT BEING SELECTED FROM THE GROUP CONSISTING OF ALUMINA HYDRATE, LIGHTLY CALCINED ALUMINA AND ALPHA-ALUMINA, AND SAID MAGNESIA-CONTRIBUTING COMPONENT BEING SELECTED FROM THE GROUP CONSISTING OF MAGNESIUM HYDROXIDE, MAGNESIUM CARBONATE, BASIC MAGNESIUM CARBONATE AND LIGHTLY CALCINED MAGNESIUM OXIDE, SAID ADMIXTURE ADDITIONALLY CONTAINING A MINOR AMOUNT OF A FLUORINE-CONTAINING MATERIAL IN THE RANGE 0.2-4.0% BYWEIGHT, OXIDE BASIS, WHEN SAID ALUMINA-CONTRIBUTING COMPONENT IS SUBSTANTIALLY FREE OF ALPHA-ALUMINA, CALCINING SAID ADMIXTURE AT A TEMPERATURE IN THE RANGE FROM ABOUT 850*C. TO ABOUT 1250*C. AND RECOVERING THE RESULTING CALCINED REACTION PRODUCT CONSISTING CHIEFLY OF MAGNESIA SPINEL, SAID FLUORINE-CONTAINING MATERIAL BEING CAPABLE OF LIBERATING HYDROGEN FLUORIDE DURING THE CALCINING OPERATION.
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) | 1970-02-13 | 1970-08-15 | 1971-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-02-13 | 1974-08-15 | 1975-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-02-13 | 1978-08-15 | 1979-02-14 | $7700.00 | Window Closed / Lapsed |