Deoxidation of Titanium Using Cerium Metal and Its Oxyhalide Formation

The recyclingRecycling and secondary recovery of titaniumTitanium (Ti) scraps requires the direct removal of oxygen (O) from the Ti scraps. Although several deoxidation techniques for Ti have been developed, the strong affinity between Ti and O limits their cost-effectiveness. In this study, we develop a new deoxidation process for Ti using cerium (Ce) metal, which is the most abundant and cost-effective rare earth element. Thermodynamic analysis suggests that the deoxidation through the formation of Ce oxyhalides in halide fluxes containing Ce ions enables the production of Ti with extremely low O concentrations. We experimentally demonstrate that the formation reaction of CeOCl with Ce metal can deoxidize Ti metal and produce highly pure Ti with 100 mass ppm O or below, which is lower than the O concentration of the virgin Ti produced by the Kroll process. This deoxidation process with Ce metal enables the recyclingRecycling and secondary recovery of Ti scraps contaminated with O.