The effect of slag alkaline and acidic oxides on the compounds of spinel magnesia - coromite refractory in copper smelting anod furnace

MgO – Cr2O3 Refractories are used in Refining Furnaces of Copper Smelters. These Alkaline Refractories in contact with Slag Alkaline and Acidic Oxides and in 1350 oC Temperature are extremely influenced by molten Slag, in this case the high dencity layer of Slag can be seen inside the Refractory Spinel and Periclase grains. In MgO – Cr2O3 Refractories, the penetration of Copper, Iron Oxides and Silica result in the growth of Spinel Magnesia Chromite (Fe,Mg)(Cr,Al,Fe)2O4 and formation of Phase Magnesium Ferrite (Fe2MgO4), in such a way that the Refractoriness temperature of penetrated area decrease from 1900 to 1400 oC and the Bonding Structure of Refractory changes to Liquid from Solid. The results of studies done by Scanning Electron Microscopy (SEM) and phase analyzer (XRD) showed that the tested Refractory Materials, the formation of Fe2SiO4 easy melting Silcate phase and Magnesium Ferrite Alkaline phase are distinguished as the factory of Chamical Corrosion. According to the obtained results the Refractory with the higher Molecular density is less affected by penteration of Alkaline and Acidic phases of Slag.