Manufacturing of Titanium Phosphide though Carbothermic Phosphorization from Titanium Dioxide, and Its Thermal Decomposed Product

Carbothermic processing is not only useful for ironmaking, it is also effectively used for processing of many non-ferrous materials such as titanium. Titanium nitride (TiN) and titanium disulfide (TiS2) are useful intermetallic compounds with lower thermal decomposition temperatures than oxides, promoting suitable applications in metallurgical processing though thermal decomposition. Furthermore, titanium phosphide (TiP) exhibits comparably low decomposition temperature. Thus, we have investigated that the manufacturing efficiency of TiP though carbothermic reaction similar with the TiN and TiS2. Titanium dioxide (TiO2) as the start material is mixed with graphite and subjected to carbothermal reduction and phosphorization at 1630 K by supplying phosphorus gas in a quartz reaction tube heated by a conventional electric furnace. Further, to investigate efficiency of the thermal decomposition, the obtained TiP is heat treated by arc flame. The thermally decomposed product, exhibiting a lustrous surface, is analyzed using X-ray diffractometry, and the diffraction pattern of metallic titanium is found together with the reduced titanium phosphide, Ti5P3, whereas starting material is titanium dioxide.