Ilmenite is the most abundant mineral for the extraction of titanium. It contains more than 50% TiO₂ along with iron, silica and alumina. The spinel structure of ilmenite (FeO·TiO₂) is such that iron is bound in the lattice of TiO₂ matrix. To remove iron from the ilmenite is a major task for process metallurgists. Various processes have been applied to remove this iron. One of them is reduction and leaching. The carbon containing pellets and environment of Jhama coal reduces the iron oxide to metallic state. This metallic iron is then leached in dilute hydrochloric acid (20% vol) and a greenish color leach liquor is obtained. The pH of the leach liquor solution is found to be 0.31. This leach liquor contains hydrochloric acid and iron as ferrous chloride. These acid and solid masses were separated by hydrothermal process in the present investigation. The residue containing ferrous chloride was characterized with the help of XRD and EPMA. During the experiment it was found that complete separation of HCl and FeCl₂ is feasible. The final pH of separated HCl is found to be 1.66 and it is suitable for reuse in the leaching of reduced ilmenite and the process makes a loop. The purity of ferrous chloride is in line with commercial grade which is a saleable product.

钛铁矿是提取钛最丰富的矿物。它包含超过50％的TiO ₂以及铁，二氧化硅和氧化铝。钛铁矿（FeO·TiO ₂）的尖晶石结构使得铁结合在TiO ₂的晶格中矩阵。从钛铁矿中除去铁是冶金学家的主要任务。已经应用了各种工艺来去除该铁。其中之一是减少和浸出。Jhama煤的含碳颗粒和环境将氧化铁还原为金属态。然后将该金属铁浸入稀盐酸（20％体积）中，得到绿色的浸出液。发现浸出液的pH为0.31。该浸出液含有盐酸和铁，如氯化亚铁。在本研究中，这些酸和固体物质是通过水热法分离的。借助XRD和EPMA对含氯化亚铁的残留物进行了表征。在实验过程中，发现HCl和FeCl ₂完全分离是可行的。发现分离出的HCl的最终pH为1.66，适用于在还原钛铁矿的浸出中重复使用，该过程形成了一个循环。氯化亚铁的纯度与可销售的商品级产品相符。