Stabilization of MgCr 2O 4 spinel in slags of the SiO 2-CaO-MgO-Cr 2O 3 system Article uri icon

abstract

  • The objective of this study is to analyze the effect of MgO content and the slag basicity on the stability of the mineralogical species of the SiO 2-CaO-MgO-Cr 2O 3 system. Slag samples were prepared in equilibrium at 1600°C under reducing conditions (pO 2= 10 -9 atm). The MgO content ranged from 0 to 12 mass%25, Cr 2O 3 was 10%25 and the slag basicity was held at 1 and 1.5. A thermodynamic analysis was carried out to estimate the most stable mineral phases in the slag. Experimental and calculated results show that Cr 2O 3 is mainly bound into MgCr 2O 4 spinel phase, even at low MgO content. SEM-EDS results show the evidence of three crystalline structures: (A) Octahedrons which correspond to MgCr 2O 4 spinel-type compound; (B) Elongated crystals which belong to calcium silicate compounds and (C) Massive grains that correspond to calcium silicates with impurites of Mg and Cr that did not crystallize completely.

publication date

  • 2006-01-01