Aeration leaching was used to obtain synthetic rutile from a reduced ilmenite. The reduced ilmenite, obtained from the carbothermic reduction of ilmenite concentrate in a rotary kiln at about 1100 °C, contained 62.88% TiO₂ and 28.93% Metallic iron. The particle size was about 200 μm and the size distribution was uniform. The effects of NH₄Cl and HCl concentrations, stirring speed, and aeration leaching time on the extent of removal of metallic iron from the reduced ilmenite were studied at room temperature. The results revealed that aeration leaching is feasible at room temperature. When using the NH₄Cl system, the metallic iron content was reduced to 1.98% in synthetic rutile, but the TiO₂ content only reached 69.16%. Higher NH₄Cl concentration did not improve the leaching. Using 2% NH₄Cl with 3% HCl, we were able to upgrade the synthetic rutile to 75%, with a metallic iron content as low as 0.14% and a total iron content of about 4%. Synthetic rutile could be upgraded to about 90% using HCl solution alone. HCl and NH₄Cl are both effective on the aeration leaching process. However, within the scope of this experiment, hydrochloric acid is more efficient in aeration leaching.

中文翻译：

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曝气浸出法从还原钛铁矿中去除金属铁

使用曝气浸提从还原的钛铁矿中获得合成金红石。通过在约1100℃下在回转窑中对钛铁矿精矿进行碳热还原而获得的还原钛铁矿包含62.88％的TiO ₂和28.93％的金属铁。粒度为约200μm，并且粒度分布均匀。在室温下研究了NH ₄ Cl和HCl浓度，搅拌速度和曝气浸出时间对还原钛铁矿中金属铁去除程度的影响。结果表明，在室温下进行曝气浸出是可行的。当使用NH ₄ Cl体系时，合成金红石中的金属铁含量降低到1.98％，而TiO ₂含量仅达到69.16％。高NH₄ Cl浓度不能改善浸出。使用2％NH ₄ Cl和3％HCl，我们能够将合成金红石提高到75％，金属铁含量低至0.14％，总铁含量约为4％。单独使用HCl溶液可以将合成金红石提高到约90％。HCl和NH ₄ Cl均对曝气浸出过程有效。但是，在该实验范围内，盐酸在曝气浸出中更有效。