Caustic conversion process

Abstract

The disclosure relates to processes for extracting lithium from an uncalcined lithium-bearing silicate and recovering a lithium salt therefrom. A slurry of the uncalcined lithium-bearing silicate and a caustic solution is heated in an autoclave to provide a Li-rich sodalite phase. The Li-rich sodalite phase is leached with a dilute acid to produce a lithium-rich pregnant liquor. Various subsequent processes to treat the lithium-rich pregnant liquor to recover a lithium salt, such as lithium phosphate, lithium carbonate, lithium sulphate or lithium hydroxide, are described.

Dependencies are inferred from the claim text.