Effects of La2O3 on the viscosity of copper smelting slag and corrosion resistance of magnesia refractory bricks

The rotating method is carried out to investigate the effects of La2O3 content (0–4 wt%) on the viscosity of copper smelting slag at high temperatures, the apparent activation energy is evaluated according to the Arrhenius equation and the structural characterization of this quenched slag is characterized by Raman spectroscopy. Meanwhile, the corrosion resistance of copper smelting slag with different content of La2O3 on magnesia refractory bricks is researched by employing a static crucible method. The experimental results show that the viscosity of copper smelting slag decreased with the La2O3 ratio increases from 0 to 3 wt% in a certain temperature range, which is because La2O3 simplifies the structural units of [SiO4] tetrahedral groups. However, the melt viscosity increases after add 4 wt% La2O3, the reason is that more La2O3 addition improves the structural compactness of [SiO4] tetrahedral groups in the molten slag due to the strong accumulation effect of La3+. Observation of the corroded samples found that the corroded magnesia refractory brick has a lower penetration index when the copper smelting slag with the content of 4 wt% La2O3. Therefore, the copper smelting slag containing 4 wt% La2O3 has a higher viscosity, and thus impeded the penetration behavior of copper smelting slag on magnesia refractory bricks.