Patent · US Expired

Desulfurization of coal

US4297108A · kind A · utility

7Cited by
10References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 22, 1980
Grant dateOct 27, 1981
Priority date
Expiry dateApr 22, 2000

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10L9/02
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Pyritic sulfur, organic sulfur and elemental sulfur are removed from coal by subjecting an aqueous slurry of coal to flotation for removal of most of the pyritic sulfur after which the coal obtained from the flotation is treated with dilute nitric acid which oxidizes any remaining pyritic sulfur and most of the organic sulfur, thus solubilizing the sulfur and reducing the sulfur content thereof. This coal can be filtered, washed and dried, if desired. Further reduction of organic sulfur is obtained by chemical treatment with unsaturated hydrocarbons which bind the organic sulfur thus lowering the sulfur content of the coal sufficiently so that the final product meets all requirements for use for power plants as well as for the metallurgical industry.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.