US4155716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for removing sulfur from coal
Assignee: Atlantic Richfield Co
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Filing: 1978-01-03
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Granted: 1979-05-22
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Expires: 1998-01-03
Abstract
Abstract A process for reducing the sulfur content of coal comprising the steps of: (1) contacting coal particles with a silicate selected from the group consisting of alkali metal silicates, alkaline earth metal silicates and mixtures thereof in an aqueous medium to reduce the sulfur content of the coal; and (2) recovering coal particles of reduced sulfur content.
Inventors
- 👤 Jui-Yuan Sun
- 👤 Jin S. Yoo
- 👤 Emmett H. Burk, Jr.
- 👤 George P. Masologites
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:29
CPC Classifications
C; C10; C10L; C10L9/00; C10L9/02
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
57 words
A process for reducing the sulfur content of coal comprising the steps of: (1) contacting coal particles with a silicate selected from the group consisting of alkali metal silicates, alkaline earth metal silicates and mixtures thereof in an aqueous medium to reduce the sulfur content of the coal; and (2) recovering coal particles of reduced sulfur content.
Claim 2
Dependent Claim
57 words
A process for reducing the sulfur content of coal comprising the steps of: (1) contacting coal particles with a silicate selected from the group consisting of alkali metal silicates, alkaline earth metal silicates and mixtures thereof in an aqueous medium to reduce the sulfur content of the coal; and (2) recovering coal particles of reduced sulfur content.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the contacting occurs at elevated temperature.
Claim 4
Dependent Claim
20 words
The process of claim 2 wherein the elevated temperature is a temperature of from about 100° C. to 500° C.
Claim 5
Dependent Claim
19 words
The process of claim 2 wherein the coal is contacted for a period of 5 minutes to 5 hours.
Claim 6
Dependent Claim
13 words
The process of claim 4 wherein the silicate is an alkali metal silicate.
Claim 7
Dependent Claim
14 words
The process of claim 4 wherein the silicate is an alkaline earth metal silicate.
Claim 8
Dependent Claim
18 words
The process of claim 4 wherein the silicate is a mixture of alkali and akaline earth metal silicates.
Claim 9
Dependent Claim
16 words
The process of claim 4 wherein the temperature is from about 150° C. to 400° C.
Claim 10
Dependent Claim
18 words
The process of claim 4 wherein the aqueous medium contains from about 0.1% to 20%, by weight, silicate.
Claim 11
Dependent Claim
24 words
The process of claim 5 wherein the alkali metal silicate is selected from the group consisting of potassium silicate, sodium silicate and mixtures thereof.
Claim 12
Dependent Claim
23 words
The process of claim 6 wherein the alkaline earth metal silicate is selected from the group consisting of calcium silicate and magnesium silicate.
Claim 13
Dependent Claim
13 words
The process of claim 10 wherein the alkali metal silicate is sodium silicate.
Claim 14
Dependent Claim
25 words
The process of claim 12 wherein the sodium silicate is selected from the group consisting of sodium metasilicates, sodium disilicates, sodium orthosilicates and sodium pyrosilicates.
Claim 15
Dependent Claim
12 words
The process of claim 13 wherein the sodium silicate is sodium metasilicate.
Claim 16
Dependent Claim
13 words
The process of claim 1 wherein steps (1) and (2) are successively repeated.
References Cited (Backward Citations)
US1668643A
Cited
GB352444A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-21 | 1982-11-20 | 1983-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-21 | 1986-11-20 | 1987-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-21 | 1990-11-20 | 1991-05-22 | $7700.00 | Window Closed / Lapsed |