Patent · US Expired

Process for producing sodium fluoride from sodium silicofluoride

US4057614A · kind A · utility

2Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 3, 1976
Grant dateNov 8, 1977
Priority date
Expiry dateNov 3, 1996

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2006/82
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process for producing sodium fluoride from sodium silicofluoride in which sodium silicofluoride is added to an ammonium fluoride solution for double decomposition reaction to obtain a slurry containing sodium fluoride as crystals and ammonium silicofluoride in dissolved form, and the solution from which the sodium fluoride crystals have been removed is added with ammonia to decompose the ammonium silicofluoride into silica and ammonium fluoride. The ammonium fluoride obtained by the decomposition is recycled to the double decomposition step. Alternatively, the ammonium fluoride is reacted with a sodium salt for recovery as sodium fluoride.

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