Ti is produced by the Kroll method, mainly by carbothermic chlorination, magnesiothermic reduction, and vacuum distillation, which result in complex processes, low efficiency, and high cost. Although Ti has many excellent properties, its high production costs limit its widespread applications. There is an urgent need to develop new Ti extraction processes to reduce the cost of Ti production. In this study, we propose a new method for the direct preparation of low-oxygen Ti powder from TiO 2 using Mg as a reducing agent and the formation of CeOCl (2Mg ( l ) + TiO 2 ( s ) + 2CeCl 3 ( l ) = Ti ( s ) + 2CeOCl ( s ) + 2MgCl 2 ( l )). First, a deoxidization experiment of Ti with Mg as a deoxidizer was conducted, and the ability of Mg to deoxidize Ti was demonstrated. At 1273 K, when the activity of CeCl 3 was 1, the oxygen concentrations of Ti-A and Ti-B were 380 and 270 ppm, respectively. Subsequently, the TiO 2 reduction experiment was conducted using Mg as the reducing agent. The results showed that MgO activity was effectively reduced by the formation of CeOCl (MgO( s ) + CeCl 3 ( l ) = MgCl 2 ( l ) + CeOCl( s )). When the system reached the Mg/MgCl 2 /CeOCl/CeCl 3 equilibrium, low-oxygen Ti powder below 1000 ppm was directly produced from TiO 2 .
The well-crystallized mixed anions compound cerium oxychloride (CeOCl) was successfully synthesized by a high-pressure solid-state metathesis reaction. The photoluminescence experiment shows that the CeOCl, with a band gap of ∼3.05 eV, has good violet-blue emission properties. And first-principles calculations of the band structures show that CeOCl is an indirect (direct) band gap semiconductor for the spin-up (spin-down) branch. This suggests that the CeOCl can be expected to be a semiconductor material. In addition, insitu high-pressure angle-dispersive X-ray diffraction experiment reveals that the bulk modulus of CeOCl is 52.8(8) GPa, which is close to our first-principles calculations, giving that B0 = 47.6(5) GPa.