Abstract
The rate of desulphurization of pig iron by solid lime was measured by the chemical analysis of sulphur content of metal samples taken from a liquid Fe-C-S alloy in a lime crucible under CO gas atmosphere.
The experimental result was interpreted by a rate equation derived from the reaction model that the reaction proceeds with the growth of a reaction product layer and the rate-determining step is the transport of sulphur through this layer.
The effect of temperature on the rate was small, the apparent activation energy of the reaction being about 14 kcal/mole.
An addition of silicon to the alloy, contrary to the results of previous investigators, was harmful for desulphurization and this was ascribed to the formation of calcium silicate on the surface of lime.
