RATE OF DEPHOSPHORIZATION OF LIQUID IRON BY SOLID LIME.

Dephosphorization of liquid iron by solid lime was studied by melting metal containing phosphorus in lime crucibles under gas flows of H//2O-H//2-Ar, H//2O-Ar, and O//2-Ar. The rate of reaction was determined by chemical analysis of samples taken from the bath at appropriate intervals. The results show that dephosphorization proceed at nearly constant rate. The rate increased with increase of the oxygen potential of the gases and was little affected by temperature. Under the experimental conditions studied the dephosphorization rate was determined by the rate of oxygen supply from gas to liquid iron. In the case of metals containing carbon, decarburization preferentially occurred prior to dephosphorization due to the differences of the reaction surface and of the affinity to oxygen.