Patent · US Expired

Purification of ammonium tungstate solutions

US4346061A · kind A · utility

6Cited by
7References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 31, 1981
Grant dateAug 24, 1982
Priority date
Expiry dateMar 31, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Prior to evaporative crystallization of ammonium tungstate solutions to give ammonium paratungstate (APT), an aluminum compound, e.g. aluminum sulfate solution, is added to precipitate silicon and phosphorus impurities. The yield of crystallized ammonium paratungstate is thereby increased.

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