The reactions between CO_(2) gas and liquid Fe-C alloy with different initial carbon concentrations at 1873 K were investigated using experimental results,thermodynamic equilibrium,and kinetic analysis.The average CO_...The reactions between CO_(2) gas and liquid Fe-C alloy with different initial carbon concentrations at 1873 K were investigated using experimental results,thermodynamic equilibrium,and kinetic analysis.The average CO_(2) conversion is greater than 80%when the carbon content ranges from 4.0 to 1.0 wt.%.When the carbon content decreases from 0.5 to 0.1 wt.%,the average CO_(2) conversion diminishes from 83.50%to 40.84%.This proves that CO_(2) gas and liquid Fe-C alloy reaction does not reach equilibrium under experimental conditions compared with the calculated thermodynamic data.Through the kinetic analysis,it is shown that in the medium-to high-carbon liquid Fe-C alloys,the rate-controlling step involves CO_(2) gas mass transfer or mixed rate-controlling of CO_(2) gas mass transfer with adsorption and dissociation of CO_(2) gas.In contrast,in the low-carbon liquid Fe-C alloy,carbon mass transfer occurs in the molten alloy.The critical carbon content of the rate-controlling step transformation is 0.7937 wt.%.展开更多
基金support of the National Natural Science Foundation of China(Nos.51674021,52004023)Major Science and Technology Innovation Project of Shandong Province of China(No.2019JZZY010358).
文摘The reactions between CO_(2) gas and liquid Fe-C alloy with different initial carbon concentrations at 1873 K were investigated using experimental results,thermodynamic equilibrium,and kinetic analysis.The average CO_(2) conversion is greater than 80%when the carbon content ranges from 4.0 to 1.0 wt.%.When the carbon content decreases from 0.5 to 0.1 wt.%,the average CO_(2) conversion diminishes from 83.50%to 40.84%.This proves that CO_(2) gas and liquid Fe-C alloy reaction does not reach equilibrium under experimental conditions compared with the calculated thermodynamic data.Through the kinetic analysis,it is shown that in the medium-to high-carbon liquid Fe-C alloys,the rate-controlling step involves CO_(2) gas mass transfer or mixed rate-controlling of CO_(2) gas mass transfer with adsorption and dissociation of CO_(2) gas.In contrast,in the low-carbon liquid Fe-C alloy,carbon mass transfer occurs in the molten alloy.The critical carbon content of the rate-controlling step transformation is 0.7937 wt.%.