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 P 2 O 5 and CaF 2 contents and the basicity on the viscosity of CaO–SiO 2 –Al 2 O 3 –La 2 O 3 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 P 2 O 5 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 P 2 O 5 content increased at a greater level at low basicity. The addition of CaF 2 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% P 2 O 5 , while the minimum occurred in the slag containing 5 wt% CaF 2 . P 2 O 5 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. CaF 2 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.