On the Phosphorus Distribution between Slag and Metal

It has been shown on the dephosphorization of liquid iron that the values of logγP2O5 or log (γP2O5⁄γFeO5) at 1873 K calculated from the data independently investigated and recently reported are closely related to those of the theoretical optical basicity for each slag, and these relations can be expressed in a simple single line for the case, in which slag constituents are lime, sodium oxide and several other materials. The symbol “γ” signifies the activity coefficient of slag components in mole fraction unit. The relation between the phosphate capacity and γP2O5 or optical basicity was also discussed. The phosphorus distribution between eleven kinds of slags and liquid Cu–P alloys given by Young and Floridis was analysed by the same way. It would be possible by calculation to estimate a slag composition suitable for dephosphorization, having high theoretical optical basicity.