Interfacial Rate of CO2^|^ndash;CO Reaction with the Solid Iron and Iron Oxide by Isotope Exchange Technique at 1273 K

Abstract

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 1 273 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 logkc 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.

Determination of the Rate of CO2–CO Reaction with Magnetite by Isotope Exchange Technique

“…In the previous work,16 the reaction conditions have been experimentally estimated. Therefore, in this study, the total flowrate of reaction gas was fixed at 300 mL min −1 STP, the size of sample was fixed to 16 cm 2 (both sides of 20 × 40 mm 2 ).…”

“…13 CO 2 –CO isotope exchange technique has been described in detail in many reported studies 1–13, 16–18. According to the difference of the isotopic compositions of outgoing and ingoing gases, the rate constant of CO 2 dissociation on the surface of sample expressed as Equation 1 can be calculated by Equation 2 as follows.…”

“…By the above supposition, the present results can be explained reasonably. And the previous results we achieved in wustite phase16 and the reported iron oxide‐containing slag systems2, 3, 5 has also confirmed the relationship of $k_{a} {\propto} (P_{{\rm CO}_{{\rm 2}} } /P_{{\rm CO}} )^{- 1} $ .…”

“…In our previous work,16 the ratio of CO 2 /CO were accurately controlled by a set of electronic mass flow controllers, the effects of experimental conditions including total flowrate of reaction gas, surface area of sample, and flowrate of 13 CO 2 isotope gas on the measured results of rate constant were experimentally investigated. A set of experiments were carried out with different CO 2 /CO ratios from 0.1 to 10 at 1273 K. It has been concluded that there is the different linear relationship of lg k c and lg(CO 2 /CO) in iron, wustite, and magnetite phase regions.…”

Reaction between CO₂–O₂ Mixture Gas and Fe–C Melts by Isotope Tracing Method

“…Yuewen FAN, 1) Xiaojun HU, 1) * Rong ZHU 2) and Kuochih CHOU 1) metallurgical reactions. [23][24][25] Isotope tracing method is a suitable way to distinguish the different sources by mass spectrometer detecting.…”