1992 Volume 78 Issue 9 Pages 1441-1448
The removal rates of tin and antimony in high carbon iron melt containing sulfur by evaporation have been investigated by the method of blowing argon onto the melt surface or reducing the furnace pressure. From an X-ray diffraction analysis of materials condensed, it was confirmed that tin was evaporated as SnS if sulfur coexisted but antimony was evaporated as metallic vapor. The removal rate was proportional to the 1/2 power of gas flow rate and the reciprocal of furnace pressure. An apparent activation energy for the removal process was calculated to be about 160 kJ · mol-1 from a plot of logarithm of apparent rate coefficient, R, against 1/T. This value was mainly attributed to the enthalpy change for each reaction. It was found from the results that the overall rate of removal was controlled by the diffusion rate of evaporated species in the gas phase under the present experimental conditions.