A Review on the Recovery of Titanium Dioxide from Ilmenite Ores by Direct Leaching Technologies

Abstract

ABSTRACT Pretreatment of ilmenite are required to enhance leaching efficiency of ilmenite. Strong acid leaching is promising in terms of the purity of the produced TiO2, low energy consumption and waste management. The effect of several factors on the acid leaching kinetics in reported processes was reviewed. Temperature, time and acid concentration significantly affect the dissolution of titanium and impurities in ilmenite. The addition of either iron powder or chloride/sulfate salts affects significantly the leaching rate of ilmenite. Either HCl leaching followed by solvent extraction or alkaline leaching followed by hydrolysis-calcination is recommended for the production of pure TiO2 from ilmenite.