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US3642433A
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Process for extracting aluminum compounds from dawsonite and dawsonitic oil shale
Assignee: United States Department of the Interior
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Filing: 1968-08-05
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Granted: 1972-02-15
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Expires: 1988-08-05
Abstract
Abstract Dawsonite and dawsonitic oil shales are heated to decompose the dawsonite into sodium aluminate. Water is then employed to dissolve and form an aluminate solution from which alumina can be recovered by known methods.
Inventors
- 👤 John R Dyni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:13
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/02; C01F7/04
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
25 words
The process of claim 1 wherein said dawsonite is heated in step a to above aboUt 560* C. in order to form crystalline sodium aluminate.
Claim 2
Dependent Claim
58 words
A process for recovering aluminum values from dawsonite consisting essentially of a. heating said dawsonite to a temperature of about 400* C. to about 1,000* C. for a time sufficient to drive off CO2 and H2O and convert said dawsonite to a residue containing water-soluble aluminate; and b. leaching said residue with dilute H2SO4 to extract said aluminate.
Claim 3
Dependent Claim
21 words
The process of claim 3 wherein said dawsonite is combined with oil shale, whereby said heating step drives off shale oil.
Claim 4
Dependent Claim
26 words
The process of claim 4 wherein said dawsonitic shale is heated in step a to a temperature of from about 400* C. to about 700* C.
Claim 5
Dependent Claim
58 words
A process for recovering aluminum values from dawsonite consisting essentially of a. heating said dawsonite to a temperature of about 400* C. to about 1,000* C. for a time sufficient to drive off CO2 and H2O and convert said dawsonite to a residue containing water-soluble aluminate; and b. leaching said residue with dilute HCl to extract said aluminate.
Claim 6
Dependent Claim
21 words
The process of claim 6 wherein said dawsonite is combined with oil shale, whereby said heating step drives off shale oil.
Claim 7
Dependent Claim
27 words
The process of claim 7 wherein said dawsonitic oil shale is heated in step a to a temperature of from about 400* C. to about 700* C.
Claim 8
Dependent Claim
67 words
A process for recovering aluminum values from dawsonite combined with oil shale consisting essentially of a. heating said dawsonite combined with oil shale to a temperature of about 400* C. to about 1,000* C. for a time sufficient to drive off shale oil, CO2 and H2O and convert said dawsonite to a residue containing water-soluble aluminate; and b. leaching said residue with water to extract said aluminate.
Claim 9
Dependent Claim
27 words
The process of claim 9 wherein said dawsonitic oil shale is heated in step a to a temperature of from about 400* C. to about 700* C.
References Cited (Backward Citations)
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US2973244A
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US3516787A
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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) | 1975-02-14 | 1975-08-16 | 1976-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-14 | 1979-08-16 | 1980-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-14 | 1983-08-16 | 1984-02-15 | $7700.00 | Window Closed / Lapsed |