EP0010289A1
Expired / Lapsed
EP
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Mild oxidative coal desulfurization
Assignee: Union Carbide Corp
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Filing: 1979-10-16
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Granted: —
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Expires: 1999-10-16
Abstract
Abstract A process for the removal of pyrite from coal which comprises preparing an aqueous slurry containing finely-divided coal particles; adding to the slurry an hydroxide or carbonate of an alkali or alkaline earth metal selected from the group consisting of sodium, lithium, potassium and magnesium, as well as mixtures of these hydroxides and carbonates, in amounts sufficient to continuously maintain the pH of the slurry between about 8 and 12; and then agitating the slurry whiletreating the slurry with oxygen or an oxygen-containing gas.
Inventors
- 👤 Stephen Thomas Wilson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 15:04
CPC Classifications
C; C10; C10L; C10L9/00; C10L9/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
85 words
A process for the removal of pyrite from coal which comprises preparing an aqueous slurry containing finely-divided coal particles; adding to the slurry an hydroxide or carbonate of an alkali or alkaline earth metal selected from the group consisting of sodium, lithium, potassium and magnesium, as well as mixtures of said hydroxides and carbonates, in amounts sufficient to continuously maintain the pH of the slurry between about 8 and 12; and then agitating the slurry while treating the slurry with oxygen or an oxygen-containing gas.
Claim 2
Dependent Claim
85 words
A process for the removal of pyrite from coal which comprises preparing an aqueous slurry containing finely-divided coal particles; adding to the slurry an hydroxide or carbonate of an alkali or alkaline earth metal selected from the group consisting of sodium, lithium, potassium and magnesium, as well as mixtures of said hydroxides and carbonates, in amounts sufficient to continuously maintain the pH of the slurry between about 8 and 12; and then agitating the slurry while treating the slurry with oxygen or an oxygen-containing gas.
Claim 3
Dependent Claim
25 words
The process as defined by claim 1 wherein the pH of the coal slurry is continuously maintained at a value of about 10 or 11.
Claim 4
Dependent Claim
22 words
The process as defined by claim 2 wherein the pH of the coal slurry is maintained by the addition of sodium hydroxide.
Claim 5
Dependent Claim
28 words
The process as defined by claim 2 wherein the pH of the coal slurry is maintained by the addition of a mixture of sodium hydroxide and sodium carbonate.
Claim 6
Dependent Claim
25 words
The process as defined by claim 1 wherein the temperature of the coal slurry is maintained in a range of between about 40 and 70°C.
Claim 7
Dependent Claim
25 words
The process as defined by claim 5 wherein the treatment of the slurry with oxygen or oxygen-containing gas is carried out at substantially atmospheric pressure.
References Cited (Backward Citations)
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