Interfacial Rate of CO₂–CO Reaction with the Solid Iron and Iron Oxide by Isotope Exchange Technique at 1273 K

抄録

The interfacial rate constant of CO₂–CO reaction with the solid iron and iron oxide has been measured by means of the isotope exchange reaction at 1273 K. Changing the total flowrate, the composition of CO₂/CO of gas mixture and the reaction area, the effects of experimental conditions on rate constant were investigated. Varying the CO₂/CO ratio in the range of 0.1 to 10, the dependence of rate constant on CO₂/CO ratio was studied. It is found that the relationship of the rate constant and CO₂/CO ratio can be divided to three regions represented iron, wüstite and magnetite phase field, respectively. In three phase regions, the slopes of the linear relationship of logk_c and log(CO₂/CO) were about –0.48, –1.14 and –1.71, respectively. The microstructure of reaction surface of sample was also observed by SEM, with the CO₂/CO ratio, the reacted surface became less smooth and showed the crystal morphology.