Carbothermal synthesis of titanium carbide using ultrafine titania powders

The synthesis of titanium carbide (TiC) by the carbothermal reduction of carbon coated titanium dioxide (TiO2), a novel synthesis process, and titanium dioxide (TiO2) mixed with carbon black was investigated. A high surface area (64 m2g-1) TiO2 powder consisting of anatase and rutile phases was used for starting powders. The carbon coated method is a two-step process that utilizes a precursor derived from decomposing propylene (C3H6) and depositing carbon on the TiO2 particles. TiO2 powders were also mechanically mixed with carbon black for comparison. Both starting precursors and mixtures were reacted in a tube furnace for 2 and 4 h at temperatures of 1100°C to 1550°C under 1 l min-1 flowing argon. The TiC powders were characterized using thermogravimetric analysis (TGA), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analyser, chemical analysis (oxygen and carbon) and transmission electron microscopy (TEM). The carbon coating process provides high contact area between the reactants which results in a TiC product with lower oxygen content (0.6 wt%), finer particle size (0.1 μm), and uniform shape when synthesized at 1550°C for 4 h.