Carbon Reduction And Sub-molten Salt Decomposition Combined Process For Treating Titanium Ore And Enriching Titanium Resources

China’s Panxi region has rich vanadium-titanium magnetite resources,and its titanium resources account for 90%of the country’s titanium reserves.Some of the beneficiation companies in the Panxi region use vanadium-titanium magnetite after magnetic separation operations.The obtained tailings are used as raw materials,and then re-dressing to obtain titanium medium ore.The TiO₂grade accounts for 36%to 38%of the ore,which cannot meet the requirements of direct production of sponge titanium,artificial rutile,titanium dioxide and high-titanium slag.Industrial requirements,its economic efficiency for industrial production is not high.This research topic uses titanium medium ore as the raw material.First,the titanium medium ore is mixed with a certain proportion of anthracite to prepare carbon-containing pellets.The iron element is separated through processes such as high temperature reduction and magnetic separation.Finally,high-activity potassium hydroxide is used.Sub-molten salt is the reaction medium,which effectively realizes the comprehensive utilization of mineral titanium resources in titanium.The main research contents and results are as follows:（1）The effects of reduction temperature,reduction time and carbon ratio（n _C/n_o）on the reduction of carbon bearing pellets of titanium middlings and magnetic field intensity on the content of TiO₂after magnetic separation were studied.The optimum conditions of direct reduction and magnetic separation were determined.Under the fixed conditions of a binder concentration of 3%,an additive amount of 10%,and a molding pressure of 16 MPa,the reduction temperature was 1350°C,the reduction time was 45 minutes,and the carbon ratio（n _C/n _O）=1.1,the particle size of ore powder was 180-200 mesh,the magnetic field strength was 160m T.The TiO₂content in the titanium ore was increased from 33.71%to 58.7%.（2）The main phase composition of the magnetic part and the non-magnetic part of the reduced pellets after magnetic separation was investigated.It is clear that under the above-mentioned optimal direct reduction process conditions,the separation of ferro-titanium from the ore in titanium can be effectively realized.（3）Using the non-magnetic part of the titanium slag obtained by the direct reduction process as the raw material,the influence of potassium hydroxide solution concentration,reaction time,and reaction temperature on the titanium conversion rate was studied,and the optimal sub-molten salt process conditions were determined.When the potassium hydroxide solution concentration was 80%,the reaction time was 3h,and the reaction temperature was260°C,the titanium conversion rate reached 94.73%.（4）The concentration of alkali solution,reaction time,and reaction temperature have been investigated for the phase composition of the reaction product and the trend of impurity elements such as calcium,magnesium,aluminum,and silicon,which are important for the comprehensive utilization of some valuable impurity elements in titanium ore reference value.（5）The macro-kinetic equation of the chemical reaction proves that the reaction of the carbon reduction products in the potassium hydroxide sub-molten salt system conforms to the unreacted shrinking nucleus model,and the initial stage of the reaction is controlled by the interface chemical reaction.