Kinetics of CO-CO2 reaction with CaO-SiO2-FeOx melts

Measurements of the rate of interfacial reaction between CO2-CO mixtures and CaO-SiO2-FeOx slags have been made using the 13CO2-CO isotope exchange technique. Ranges of slag compositions from 0 to 100 wt pct ‘FeO’ and CaO/SiO2 between 0.3 and 2.0 were examined in the experiments. For each slag, the dependence of the apparent rate constant on temperature and equilibrium oxygen potential was studied. The relationship between the rate constant and oxygen potential was found to be in the form ka=kao(ao)-α. The parameter a, with values between 0.5 and 0.9, was dependent on the slag composition. The activation energy of the reaction was independent of iron oxide content and dependent on slag basicity.