Patent · US Expired

Purification of Bayer process liquors

US4578255A · kind A · utility

19Cited by
2References
19Claims
0Family size

Assignees

Inventors

Key dates

Filing dateDec 27, 1984
Grant dateMar 25, 1986
Priority date
Expiry dateDec 27, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2002/84
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Bayer process liquors derived from the digestion of bauxites with a caustic solution are purified by removing at least a portion of the organic impurities present in the liquors. Removal of these impurities is accomplished by treating liquor containing dispersed therein solids generated by the Bayer process or added thereto, such as red mud particles, alumina trihydrate, oxalate salt, or filter aid with an organic polymeric, water-soluble cationic quaternary ammonium salt (POLYQUAT salt) which due to its cationic nature will adhere to the surface of the dispersed solids. The organic coating or layer adhered to the solids provides a receptive surface for the organic impurities, thus allowing formation of a solid-Polyquat-organic Adduct which is easily removed from the Bayer system.

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