Characterization on Behavior of Al During the Oxidization Roasting Process of Polymetallic Ferruginous Manganese Ores

摘要

Polymetallic ferruginous manganese ores contain a variety of valuable metals, it is significant to realize the efficient utilization. Spinel-type composite ferrites with strong magnetism can be prepared from the polymetallic ferruginous manganese ores, while the impurities in the ores have certain impact on the properties of the ferrites. This study was mainly concentrated on the behavior of Al during the formation process of ferrites. It has been found that during the oxidation roasting process, Al element has occupied the octahedral gap (sit B) in spinel structure of ferrites, which reduced the magnetism property of ferrite. However, SiO_2 can improve the magnetism properties of Al-bearing manganese ferrites owing to that SiO_2 was able to transfer Al out of B sit of spinel via the chemical driving force generated by the formation of corresponding silicates from the SiO_2 and Al oxides. This work demonstrated that Al impurity can be regulated by adding SiO_2.