Isothermal Carbothermal Reduction of FeTiO3 Doped with MgO

The effect of MgO on the carbothermal reduction of FeTiO3 has been investigated using isothermal experiments. x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) techniques were used to reveal the reduction mechanism of FeTiO3 doped with MgO. The results showed that MgO could promote the reduction of FeTiO3. After doping with MgO, solid solution of Mg2+ in the FeTiO3 unit cell formed a new phase (Fe1-x,Mg-x)(2)TiO4. With increase of the MgO content, the stability of the FeTiO3 lattice and the (Fe1-x,Mg-x)(2)TiO4 structure decreased while the reaction activity increased, facilitating formation of FeTi2O5 and (Fe1-2x,Mg-2x)TiO3 and aiding reduction of (Fe1-x,Mg-x)(2)TiO4 to the orthogonal system (Fe1-2x,Mg-2x)TiO3. When the content of MgO exceeded 4%, large amounts of magnesium-titanium compounds were generated and subsequently covered unreacted particles. Meanwhile, the contact area between unreacted particles and reducing agents decreased, thereby weakening the promoting effect of MgO.