US4448584A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for removing sulfur from coal
Assignee: Atlantic Richfield Co
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Filing: 1980-08-07
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Granted: 1984-05-15
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Expires: 2000-08-07
Abstract
Abstract A process for reducing the sulfur and ash content of coal comprising the steps of: (1) contacting coal particles containing ash and iron pyrite mineral matter with a promoting amount of at least one conditioning agent capable of modifying or altering the existing surface characteristics of the pyrite under conditions to effectuate alteration or modification of at least a portion of the contained pyritic sulfur; (2) separating the coal particles from at least a portion of the pyritic sulfur while surface characteristics are altered or modified; and (3) recovering coal particles wherein the coal exhibits reduced sulfur and ash content.
Inventors
- 👤 George P. Masologites
- 👤 Jui-Yuan Sun
- 👤 Jin S. Yoo
- 👤 Emmett H. Burk, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:57
CPC Classifications
C; C10; C10L; C10L9/00; C10L9/02
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
113 words
A process for reducing the sulfur and ash content of coal comprising the steps of: (1) contacting coal particles containing ash and iron pyrite mineral matter with a promoting amount of at least one conditioning agent capable of modifying or altering the existing surface characteristics of the pyrite under conditions to effectuate alteration or modification of at least a portion of the contained pyritic sulfur, wherein the conditioning agent is an inorganic compound which can hydrolyze in water; (2) separating the coal particles from at least a portion of the pyritic sulfur while surface characteristics are altered or modified; and (3) recovering coal particles wherein the coal exhibits reduced sulfur and ash content.
Claim 2
Dependent Claim
113 words
A process for reducing the sulfur and ash content of coal comprising the steps of: (1) contacting coal particles containing ash and iron pyrite mineral matter with a promoting amount of at least one conditioning agent capable of modifying or altering the existing surface characteristics of the pyrite under conditions to effectuate alteration or modification of at least a portion of the contained pyritic sulfur, wherein the conditioning agent is an inorganic compound which can hydrolyze in water; (2) separating the coal particles from at least a portion of the pyritic sulfur while surface characteristics are altered or modified; and (3) recovering coal particles wherein the coal exhibits reduced sulfur and ash content.
Claim 3
Dependent Claim
25 words
A process of claim 1 wherein the conditioning agent is an inorganic compound which hydrolyzes in water to form a high surface area inorganic gel.
Claim 4
Dependent Claim
63 words
The process of claim 1 wherein the conditioning agent is selected from the group consisting of metal aluminates having the formula M' d (AlO 3 ) e or M' f (AlO 2 ) g , wherein M is Fe, Co, Ca, Mg, Ba, Zn, Pb or Mo; and d, e, f and g are whole numbers depending on the ionic valence of M.
Claim 5
Dependent Claim
36 words
The process of claim 1 wherein the conditioning agent is selected from the group consisting of aluminasilicates having the formula Al 2 O 3 . x SiO 2 wherein x is from about 0.5 to 5.
Claim 6
Dependent Claim
24 words
The process of claim 1 wherein the conditioning agent is selected from the group consisting of inorganic cement materials which can bind mineral matter.
Claim 7
Dependent Claim
30 words
The process of claim 1 wherein the conditioning agent is selected from the group consisting of aluminum oxide, aluminum hydroxide and mixtures thereof hydrolyzed in water forming an alumina gel.
Claim 8
Dependent Claim
24 words
The process of claim 3 wherein the conditioning agent is selected from the group consisting of calcium, magnesium and iron aluminates and mixtures thereof.
Claim 9
Dependent Claim
29 words
The process of claim 5 wherein the conditioning agent is selected from the group consisting of portland cement, natural cement, masonry cement, pozzolan cement, calcined limestone and calcined dolomite.
Claim 10
Dependent Claim
13 words
The process of claim 8 wherein the cement material is hydrolyzed portland cement.
Claim 11
Dependent Claim
26 words
The process of claim 1 wherein contacting coal particles with conditioning agent is at a temperature in the range from about 0° C. to 100° C.
Claim 12
Dependent Claim
20 words
The process of claim 10 wherein the temperature is in the range of from about 20° C. to 100° C.
Claim 13
Dependent Claim
25 words
The process of claim 1 wherein the coal particles are contacted with conditioning agent for a period of from about 1 minute to 2 hours.
Claim 14
Dependent Claim
21 words
The process of claim 12 wherein the coal particles are contacted from a period of from 10 minutes to 1 hour.
Claim 15
Dependent Claim
22 words
The process of claim 1 wherein the amount of conditioning agent is from about 0.05% to 15% by weight of mineral matter.
Claim 16
Dependent Claim
19 words
The process of claim 1 wherein a dense media is employed in separating the coal particles from pyritic sulfur.
Claim 17
Dependent Claim
18 words
The process of claim 1 wherein froth flotation is employed in separating the coal particles from pyritic sulfur.
Claim 18
Dependent Claim
21 words
The process of claim 1 wherein the coal is selected from the group consisting of bituminous coal and higher ranked coal.
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) | 1987-05-15 | 1987-11-14 | 1988-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-15 | 1991-11-14 | 1992-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-15 | 1995-11-14 | 1996-05-15 | $7700.00 | Window Closed / Lapsed |