Titanium extraction from titanium slag by hydrogen-assisted magnesiothermic reduction and hydrogen plasma-refining

A new method was proposed for titanium production using high titanium slag as raw material, via the combination of metal-thermal reduction and plasma-refining with hydrogen assistance. Titanium hydride products with oxygen content of 0.9 wt% was obtained by hydrogen-assisted magnesiothermic reduction of high titanium slag at a relatively low temperature (750 °C) for 4 h. Moreover, hydrogen-plasma arc refining was adopted to highly efficient removal of impurities in titanium hydride. The main metallic impurities (Al, Fe and Mn) bringing by titanium slag were removed from 1.23 to 2.33 wt% to below 40 ppm after refining at a current intensity of 150 A for 40 min. The removal rates of aluminum, iron and manganese all reached 99%. The hydrogen facilitates deoxidation and promotes impurity-removal by reducing the stability of Ti–O solid solution and forming hydrides, respectively. Using the low-cost and high-yield titanium slag as raw material, this study proposed a complete and highly efficient method for titanium production.