Kinetics of Carbon Dissolution of Coke in Molten Iron

The effect of temperature on the dissolution rate of carbon from coke in molten iron was investigated using a sampling technique in the temperature range of 1723 K to 1923 K (1450 °C to 1650 °C). The dissolution rate of carbon from coke in molten iron increased as the temperature increased. At 1923 K (1650 °C), the rate-determining step was the mass transfer of carbon in the boundary layer adjacent to the metal-carbon interface. At 1723 K (1450 °C), the rate-determining step changed from the mass transfer to the interfacial chemical reaction as the reaction proceeded. At 1823 K (1550 °C), both reaction steps affected the apparent reaction rates. Sulfur dissolution did not affect the carbon dissolution rates in molten iron, so it was considered that the sulfur adsorption at the metal/coke interface was not so significant. The apparent activation energy of the carbon dissolution of coke in molten iron was estimated to be 442 kJ/mol.