Extraction of Ti Powder from Ti–MgO–Mg(–CaO) Cakes Produced by Magnesiothermic Reduction

Resumo

The extraction of Ti powder from SHS-produced Ti–MgO–Mg(–CaO) cakes by treatment in leaching solutions (HNO₃, HCl, and NH₄Cl) was explored and optimized in relation to such factors as concentration of leaching agent, leaching temperature, chemical resistance of target Ti powder, and extent of byproducts extraction. The type of leaching solution was found to affect the size, structure, and morphology of resultant Ti powder. Best results were obtained at 70°C with aqueous solutions of: (1) the nitric acid taken in a 6-fold excess to the Mg content of combustion product and (2) the ammonium chloride taken in a 20-fold excess to nominal Mg content.