Patent · US Expired

Deprotonation of an alkylphenyl acid phosphate extractant

US4325918A · kind A · utility

7Cited by
1References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 31, 1979
Grant dateApr 20, 1982
Priority date
Expiry dateAug 31, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22B60/0265
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Uranium in wet-process phosphoric acid in the tetravalent state is extracted with an alkylphenyl acid phosphate extractant. The uranium in the pregnant extractant is then oxidized to the hexavalent state and stripped with a phosphoric acid stripping solution. Hydrolysis of the extractant is decreased by decreasing the proton concentration of the extractant which results from acidic impurities, e.g., sulfuric acid and fluorosilicic acid, originally present in the wet-process phosphoric acid. The proton concentration of the extractant is reduced indirectly by treating the phosphoric acid strip solution (1) with reagents which react with the acidic impurities to form water and an insoluble precipitate which is removed from the stripping solution; (2) with reagents to neutralize the acidic impurities in the stripping solution; or (3) by passing the stripping solution through a suitable ion exchange column.

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