Patent · US Expired

Method of treating coal to remove sulfur and ash

US4305726A · kind A · utility

62Cited by
8References
11Claims
0Family size

Inventor

Key dates

Filing dateDec 21, 1979
Grant dateDec 15, 1981
Priority date
Expiry dateDec 21, 1999

Classification

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

Abstract

The present invention is directed to an improved method of chemically treating coal to remove sulfur and ash. It is especially adapted for use on high sulfur, refuse coal. In practice the coal is treated with hydrochloric acid and hypochlorous acid in the presence of ferric and ferrous sulfate to convert the iron pyrites to other sulfur compounds. These are then converted to various salts of calcium through neutralization with lime.

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