Effect of P 2 O 5 , CaF 2 and Basicity on the Viscosity and Structure of La 2 O 3 -Bearing Calcium–Silicate–Aluminum Slag System

The effects of the P2O5 and CaF2 contents and the basicity on the viscosity of CaO–SiO2–Al2O3–La2O3 slag systems were investigated using the rotating cylinder method during the continuous cooling process. The structural characteristics of the quenched slag samples were clarified by Fourier transform infrared and Raman spectroscopies. The results showed that the slag viscosity and break temperature gradually increased with increasing P2O5 content from 0 and 2.5 to 5 wt% at each basicity of 0.87, 1.0 or 1.17; meanwhile, the viscosity increased as the P2O5 content increased at a greater level at low basicity. The addition of CaF2 obviously reduced the viscosity and break temperature of slag. The increase in the basicity from 0.87 and 1.0 to 1.17 decreased the viscosity of the slags under the present composition range, but raised the break temperature. The maximum viscosity reduction by the basicity occurred in the slag containing 5 wt% P2O5, while the minimum occurred in the slag containing 5 wt% CaF2. P2O5 acted as a network former in the molten slag and increased the polymerization of the silicate and phosphate complex anions, corresponding to an increase in the slag viscosity. CaF2 played a major role in the depolymerization of the silicate and phosphate complex anions in this study.Kindly check and confirm the edit made in the title.The title was no problem.