Desulfurization of coal
AssigneeUnion Oil Company of California
InventorsJ. Wayne Miller, Mark J. Anderson
Life of this patent
Estimating the term…
Abstract
A process for reducing the amount of pyritic, organic and sulfate sulfur in coal and other carbonaceous materials by contacting sulfur-containing coal or carbonaceous material with hydrogen, transition metal salts and a buffer under increased temperature and pressure. Pyritic sulfides are reduced to ferrous sulfides and organic sulfides are converted to metal sulfides; the sulfides are, then, leached from the coal or carbonaceous material utilizing an acid solution. Alternatively, a metal compound may be added to the acid solution to promote the formation of hydrogen sulfide.
Claims31
A process for desulfurizing coal and other carbonaceous materials which contain pyritic sulfur, organic sulfur and sulfate sulfur which comprises:
- contacting an aqueous slurry of said coal or carbonaceous material with a transition metal salt, hydrogen and a buffer that buffers within the pH range of from about 4 to about 10 under reaction conditions;
- and contacting said coal or carbonaceous material with an acid.
A process for desulfurizing coal and other carbonaceous materials which contain pyritic sulfur, organic sulfur and sulfate sulfur which comprises contacting an aqueous slurry of said coal or carbonaceous material, a transition metal salt, hydrogen, and a buffer that buffers within the pH range of from about 4 to about 10 at a temperature of from about 200.degree. F. to about 450.degree. F. and a pressure of from about 100 psig to about 4000 psig, for about 30 minutes to about 5 hours, raising the temperature from about 450.degree. F. to about 700.degree. F. for about 30 minutes to about 25 hours;
- and contacting said coal or carbonaceous material with an acid.
Dependencies are inferred from the claim text.