The Research On The Effects Of Pretreatment On Structure And Properties Of Panzhihua Ilmenite

Ilmenite is used as the main raw material to produce titanium products for its abundant resources and low cost. There are more and more researches on its comprehensive utilization. The way to manufacture rich-titanium material is the hot spot. Using ilmenite to prepare electrode materials for super capacitor is a new aspect. Based on the structural and mineralogical properties of Panzhihua ilmenite concentrate, this work focused on structural changes and hydrochloric acid leaching of single minerals in ilmenite concentrate by ball milling and oxidation-reduction. Nano-FeTiO3was prepared by "ball milling-alkine leaching" process.The preatment of "oxidation-reduction-milling" was adopted to study the acid leaching behaviors of Ca, Mg and Fe in ilmenite, titanaugite and plagioclase. XRD, SEM and EDS were used to characterize the structure changes of these minerals under different pretreatments. The acid leaching behaviors of such single minerals were studied. The results showed that the phase structure and the surface topography of ilmenite were changed obviously after oxidation-reduction treatment. Fe migrated to the surface and its leaching extraction enhanced significantly. The surface topography of ilmenite became loose with micro-fissures. The phase structure of titanaugite wasn’t changed, but the surface topography became loose with lots of fissures and holes. The leaching extraction of Fe, Ca, Mg also increased significantly. The surface topography and phase structure of plagioclase weren’t altered and the leaching extraction of Ca also wasn’t changed. The oxidation-reduction treatment strengthened the process of mechanical activation for ilmenite and titanaugite, but made no use for plagioclase.The kinetics results indicated that the leaching curves of untreated ilmenite concentrate, the ball milled ilmenite concentrate and oxidized-reduced-milled ilmenite concentrate followed the kinetic model of the shrinking core model. The apparent activation energy of the leaching reaction of Fe of the untreated ilmenite concentrate was57.92kJ/mol. The leaching reaction of ball milled ilmenite concentrate included the leaching of activated layer and unactivated layer. The activity in leaching reaction decreased with the frontier reaction surface moving to the deep layer of the solid. The apparent activation energy of Fe increased from16.53kJ/mol to19.76kJ/mol. The leaching reaction of oxidized-reduced-milled ilmenite concentrate was similar, but the apparent activation energy decreased to8.71kJ/mol.Nano-FeTiO3was prepared by "ball milling-alkaline leaching". The influences of ball-milling modes, ball-milling time, alkaline treatment on the morphology and phase change of the Nano-FeTiO3were discussed by XRD, SEM. The supercapacitor property was also investigated by cyclic voltammetry (CV), constant charge/discharge test and electrochemical impedance spectra (EIS). The results indicated that the capacity of Nano-FeTiO3electrode mainly resulted from the pseudocapacitive capacitance and it exhibited a specific capacitance of176.3F/g at the current of0.1A/g in the1mol/L KOH solution.