Patent · US Expired

Demineralization of coal

US4299684A · kind A · utility

1Cited by
11References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 30, 1980
Grant dateNov 10, 1981
Priority date
Expiry dateJun 30, 2000

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB03B9/005
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Disclosed is a method for comminuting and simultaneously removing mineral matter from coal by first treating the coal with a quaternary base solution, such as tetrabutylammonium hydroxide, then physically separating the mineral matter by any conventional separation technique based on the density differences of two materials.

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