Carbochlorination kinetics of titanium dioxide with carbon and carbon monoxide as reductant

Kinetic study of the chlorination of titanium dioxide (rutile and anatase) was carried out in a fixed-bed reactor at temperature ranging from 800 degr ees C to 1000 degrees C and normal pressure. In our experiment, titanium di oxide powder and gaseous chlorine with carbon or carbon monoxide as reducta nt were used. The products of the reaction are all in gaseous phase under t he temperatures and pressure studied. With CO as reductant, reaction is of noncatalytic gas-solid nature and experimental data fit the shrinking core model. When using C as reductant, solid-solid reaction is involved. Reactiv ity is highly enhanced by solid carbon and it is concluded that an activate d C-TiO2-Cl complex contributes to the enhanced reactivity. A reaction mode l based on phase boundary control applies to the experimental data. Thermod ynamic analysis supports the experimental observation.