CH₄-H₂-H₂OおよびCO-CO₂系におけるアイアンカーバイドの相平衡

抄録

Phase diagrams of Fe, FeO, Fe₃O₄, Fe₂C and Fe₃C in CH₄-H₂-H₂O and CO-CO₂ gas mixtures were made by using thermodynamic data at every 50°C in the temperature range from 550 to 850°C. On the basis of these diagrams, experimental conditions were determined. The reaction experiments were carried out by using fluidized bed or fixed bed reactor with the sample of two kinds of ore (dense and porous, 0.4-0.5 mm in diameter). The thermodynamic date used can be recommended because the experimental results under some conditions near the main phase boundary agreed well with the estimated one. It was confirmed that Fe₃C was produced via Fe₃O₄ in CO-CO₂, gas mixtures at 550°C. However, the reaction rete was very slow. This Fe₃C hardly decomposed to Fe and C. When the steam of 5 vol % or more was included in the CH₄-H₂-H₂O gas mixtures. Fe₃C was not generated in 0.1 MPa at all.