Leaching titaniferous magnetite concentrate with alkali solution of high concentration under high temperature and high pressure was utilized to improve the grade of iron in iron concentrate and the grade of TiO₂ in titanium tailings. The titaniferous magnetite concentrate in use contained 12.67% TiO₂ and 54.01% Fe. The thermodynamics of the possible reactions and the kinetics of leaching process were analyzed. It was found that decomposing FeTiO₃ with NaOH aqueous solution could be carried out spontaneously and the reaction rate was mainly controlled by internal diffusion. The effects of water usage, alkali concentration, reaction time, and temperature on the leaching procedure were inspected, and the products were characterized by X-ray diffraction, scanning electron microscope, and energy dispersive spectroscopy, respectively. After NaOH leaching and magnetic separation, the concentrate, with Fe purity of 65.98% and Fe recovery of 82.46%, and the tailings, with TiO₂ purity of 32.09% and TiO₂ recovery of 80.79%, were obtained, respectively.

利用高温高压碱液浸出钛磁铁矿精矿，提高铁精矿中铁品位和钛尾矿中TiO ₂品位。使用中的钛磁铁矿精矿含有 12.67% TiO ₂和 54.01% Fe。分析了可能发生的反应的热力学和浸出过程的动力学。发现分解 FeTiO ₃NaOH水溶液可自发进行，反应速率主要受内扩散控制。考察了用水量、碱浓度、反应时间和温度对浸出过程的影响，并分别通过X射线衍射、扫描电子显微镜和能谱仪对产物进行了表征。经NaOH浸出和磁选，分别得到Fe纯度为65.98%、Fe回收率为82.46%的精矿和TiO ₂纯度为32.09%、TiO ₂回收率为80.79%的尾矿。