Patent · US Expired

Process for the production of potassium chloride and magnesium chloride from carnallite

US4140747A · kind A · utility

6Cited by
10References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 20, 1977
Grant dateFeb 20, 1979
Priority date
Expiry dateOct 20, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/141
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The present invention relates to a process for the production of potassium chloride and of magnesium chloride hexahydrate (bischoffite) from carnallite or from carnallite containing sodium chloride. The process comprises heating carnallite at a temperature of between above 70.degree. C. and above 167.5.degree. C. in the presence of added water at the above former temperature or without added water (but preventing evaporation of water) at the above latter temperature. Solid potassium chloride is then separated. In the residual brine, carnallite is precipitated by evaporation or by lowering the temperature, and it is recycled to the starting stage. The residual solution consists essentially of magnesium chloride which is recovered as bischoffite.

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