US3962403A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for separation of nahcolite from oil shale
Assignee: ExxonMobil Oil Corp
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Filing: 1974-01-14
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Granted: 1976-06-08
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Expires: 1994-01-14
Abstract
Abstract Nahcolite-bearing oil shale ore is heated to produce a distinct color change in the nahcolite, differentiating the nahcolite from the host oil shale for optical sorting, and such sorting is then accomplished by optical sorting means.
Inventors
- 👤 Dagobert M. Wyslouzil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:48
CPC Classifications
C; C01; C01D; C01D7/00; B; B07; B07C; B07C5/00; B07C5/34; B07C5/342; B07C5/3425; B07C5/3427; C01D7/12; C01D7/123
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
63 words
A process for separation of nahcolite from nahcolite-bearing oil shale ore, comprising the steps of: heating said nahcolite-bearing oil shale ore at a temperature of from about 100°C to about 1000°C for a time sufficient to convert at least some of the surface of said nahcolite to a lighter-colored product; and optically sorting to separate said lighter-colored product from the remaining oil shale.
Claim 2
Dependent Claim
63 words
A process for separation of nahcolite from nahcolite-bearing oil shale ore, comprising the steps of: heating said nahcolite-bearing oil shale ore at a temperature of from about 100°C to about 1000°C for a time sufficient to convert at least some of the surface of said nahcolite to a lighter-colored product; and optically sorting to separate said lighter-colored product from the remaining oil shale.
Claim 3
Dependent Claim
42 words
The process of claim 1 wherein said nahcolite-bearing oil shale ore is in the form of particles of from about 1/4 inch to about 3/4 inch in size and said heating is at a temperature of from about 150°C to about 200°C.
Claim 4
Dependent Claim
21 words
The process of claim 2 wherein said heating is for a time of from about 15 minutes to about 30 minutes.
Claim 5
Dependent Claim
16 words
The process of claim 1 wherein said optical sorting includes at least two stages of sorting.
Claim 6
Dependent Claim
12 words
The process of claim 1 wherein said optical sorting comprises area sorting.
Claim 7
Dependent Claim
17 words
The process of claim 1 wherein substantially all of said nahcolite is converted to said lighter-colored product.
Claim 8
Dependent Claim
83 words
A process for separation of nahcolite from nahcolite-bearing oil shale ore, comprising the steps of: heating said nahcolite-bearing oil shale ore at a temperature of from about 100°C to about 1000°C for a time sufficient to convert at least some of the surface of said nahcolite to sodium carbonate having a distinctly lighter color than the surface of the remaining oil shale; and optically sorting said heated nahcolite-bearing oil shale ore to separate a lighter-colored converted nahcolite fraction from the remaining oil shale.
Claim 9
Dependent Claim
83 words
A process for separation of nahcolite from nahcolite-bearing oil shale ore, comprising the steps of: heating said nahcolite-bearing oil shale ore at a temperature of from about 100°C to about 1000°C for a time sufficient to convert at least some of the surface of said nahcolite to sodium carbonate having a distinctly lighter color than the surface of the remaining oil shale; and optically sorting said heated nahcolite-bearing oil shale ore to separate a lighter-colored converted nahcolite fraction from the remaining oil shale.
Claim 10
Dependent Claim
42 words
The process of claim 7 wherein said nahcolite-bearing oil shale ore is in the form of particles of from about 1/4 inch to about 3/4 inch in size and said heating is at a temperature of from about 150°C to about 200°C.
Claim 11
Dependent Claim
35 words
The process of claim 8 wherein said heating is for a time of from about 15 minutes to about 30 minutes and substantially all of the surface of said nahcolite is converted to sodium carbonate.
Claim 12
Dependent Claim
16 words
The process of claim 7 wherein said optical sorting comprises a plurality of area sorting stages.
Claim 13
Dependent Claim
23 words
The process of claim 7 wherein said heating is for a time sufficient to convert substantially all of said nahcolite to sodium carbonate.
References Cited (Backward Citations)
US3133010A
Cited
US3097744A
Cited
US3479133A
Cited
US3821353A
Cited
US3819805A
Cited
US3795310A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-08 | 1979-12-08 | 1980-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-08 | 1983-12-08 | 1984-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-08 | 1987-12-08 | 1988-06-08 | $7700.00 | Window Closed / Lapsed |