Role of some technological parameters during carburizing titanium dioxide

The influence of technological parameters is followed during the carbothermal synthesis of titanium carbide from the dioxide. The carbon grain size, the homogeneity of the carbon/oxide mixtures and the ventilation of the powdersʹ beds are the most important conditions for a rapid reaction. The oxide grain size, the mixing method and the compactness of the mixture has no influence, or very little. These results are explained by the carburizing mechanism where the Boudouardʹs reaction: C+CO2→2CO plays a central role. This reaction is more rapid when fine carbon is used and when the carbon monoxide is eliminated as soon as formed. These conditions are those required for a complete synthesis of the carbide by: TiO2+3C→TiC+2CO for mixtures having the stoichiometric composition.