Crystal structure of calcium and aluminium silicoferrite in iron ore sinter

The crystal structures of real and synthetic iron ore sinters were compared. In the Fe2O3-CaO-Al2O3SiO2 system, the crystal structure of a synthetic solid solution of CaO.2Fe(2)O(3) (CF2) was studied by X-ray powder diffraction. As the Al2O3 content in pure CF2 increased, the formation of hemicalcium ferrite. increased. On the other hand, CF2 content decreased and hematite increased as the SiO2 content increased. The crystal structure of CF2 with Al2O3 and SiO2 (calcium and aluminium silicoferrite, also known as silicoferrite of calcium and aluminium, SFCA) changed from monoclinic to triclinic, and the unit cell volume decreased when the Al2O3/SiO2 ratio increased. The solubilities of Al2O3 and SiO2 in CF2 were 5-7 wt-% and 2-4 wt-%, respectively at 1250degreesC.