Rate of Dephosphorization of Liquid Iron-Carbon Alloys by Molten Slags

Abstract

The rate of dephosphorization of liquid iron-carbon alloys by FeO-CaO-SiO₂ slaps and the effect o f NaCl or CaCl₂ added to the slaps on the reaction rate have been investigated on a laboratory scale at temperatures of 1300-1460°C. The results show that the rate and degree of dephosphorization increase by the addition of NaCl or CaCl₂ to the slag. But the degree of dephosphorization decreases with increasing temperature.
It is found that the rate of dephosphorization of iron-carbon melt can be explained by the modified mass transfer controlled model in which mass transfer of iron and phosphorus across the slag-metal interface is controlled by diffusion while the evolution of CO gas is the chemical reaction controlled.