Study on synthesis of MgAl ₂ O ₄ spinel materials from alumina titania slag and light‐burned magnesia

Abstract Alumina titania slag (It is an industrial waste generated during the preparation of iron titanium alloys by aluminum thermal reduction method.) and light‐burned magnesia were used as raw materials to prepare MgAl 2 O 4 spinel at 1400–1600°C. Particularly, the effect of the mass ratio of alumina titania slag and light‐burned magnesia on the synthesis and densification of MgAl 2 O 4 spinel was studied. The mass ratio of alumina titania slag and light‐burned magnesia was adjusted to 100:29, 100:35, 100:41, and 100:47. Alumina titania slag was mixed with light‐burned magnesia according to above mass ratio, respectively, and pressed into billets diameter of 20 mm and height of 15 mm. The green‐body billets then were sintered at 1400–1600°C in an air atmosphere. Bulk density, apparent porosity, phase composition, and microstructure of final sintered products were analyzed. The results indicated that MgAl 2 O 4 spinel could be prepared by solid reaction of alumina titania slag and light‐burned magnesia. With the increasing magnesia content, the bulk density of samples and lattice parameters of MgAl 2 O 4 spinel increased, while apparent porosity of samples decreased. At the same time, the higher magnesia content, the more MgAl 2 O 4 spinel particles with obvious structure appeared and grew large.