Study on the Action Mechanism of Pre-oxidation on Reduction Behavior of Rock Ilmenite

Reduction is the key technological process of preparing titanium-rich material from ilmenite.This paper studied the action mechanism of pre-oxidation on reduction behavior of rock ilmenite in detail,using Panzhihua ilmenite as the experimental subject.The results show that the reduction rate of untreated rock ilmenite is slow and the pre-oxidation can increase the reduction rate effectively. This is due to the rapid transformation reaction of Fe³⁺→Fe²⁺ （FeTiO₃） at the earlier stage of reduction for pre-oxidized ilmenites.This rapid reaction produces a large number of pores and destroys the dense structure of ilmenite,which is conducive to the proceeding of reduction reaction.The rate of subsequent reduction of ilmenite is greater with higher pre-oxidation temperature and longer roasting time for pre-oxidation.Moreover,the preoxidation also makes the metallic Fe,which is produced by the subsequent reduction,have smaller grains and a more dispersed distribution.