中国有色冶金

The output of secondary aluminum ash in China is large, and the total aluminum content is not low. In the process of stacking, it is leached by rain, resulting in pollution of water and soil salinization. On the basis of previous studies, the secondary aluminum ash produced in the recycled aluminum industry was used as the main raw material, and the effect of silica content on the properties of magnesium-aluminum spinel materials sintered from secondary aluminum ash was studied by solid-phase sintering method, and the sintered products were analyzed by means of XRD, SEM and infrared spectroscopy. The results show that when the mass fraction ratio of secondary alumina ash to magnesium oxide is 1∶0.2, the secondary alumina ash can be sintered into MgAl₂O₄ spinel materials at 1400℃ and held for 3h. Silicon dioxide has an effect on the properties of MgAl₂O₄ spinel materials prepared by secondary alumina ash sintering. When 5% silicon dioxide was added, the performance of MgAl₂O₄ spinel was the best, that is, the bulk density was 2.03g/cm³, the linear change rate was 0.42 and the compressive strength was 91.1MPa. When 5%-20% silicon dioxide samples were sintered at 1400℃, the main phase of the material was MgAl₂O₄ With the increase of silica content, the intensity of MgAl₂O₄ diffraction peak decreased, thicker fibrous structure appeared in the sintered body, and the density of the material increased. The presence of appropriate silica can promote the preparation of high-performance magnesia alumina spinel materials by secondary aluminum-lime sintering. In the sintering process, both the cell constant and the cell volume of the product go through the process of first increasing and then decreasing, which is also the process of ion dissolution in and out. In this study, the secondary aluminum ash can be treated economically and efficiently, which not only reduces environmental pollution, but also solves the shortage problem of resource containing aluminum, which has a certain significance for realization of secondary aluminum ash utilization problem.