微量H₂S含有H₂-CH₄混合ガスによるペレット中炭化鉄の生成挙動

抄録

Using a thermobalance, industrial hematite pellets were reacted with H₂-CH₄ mixtures at 800950°C to produce iron carbide in the pellets. H₂S of low pressures unable to form FeS was added to the mixtures. First, reduction of iron oxides proceeded and meanwhile carbidization of metallic iron took place. The addition of traces of H₂S into gas promoted iron carbides (Fe₃C, Orthorhombic) rather than free carbon or metallic iron as final products with nearly complete carbide conversion. The higher the temperature, the larger the carbidization rates. The sulfur index in gas around i_s=0.05 provided high yields of iron carbides with low sulfur content of less than 0.05 mass% S. The tests without H₂S gave lower iron carbide contents with much free carbon (soot) or metallic iron. Initial carbidization rates of a reduced iron pellet coincided with a reaction rate model proposed earlier by Grabke.