South Ural State University (NRU), Chelyabinsk, Russia

K. I. Smirnov, Rresearcher, Laboratory of Hydrogen Technologies in Metallurgy
P. A. Gamov, Cand. Eng., Associate Prof., Acting Head of the Laboratory of Hydrogen Technologies in Metallurgy
V. S. Samolin, Postgraduate Student, Dept. of Pyrometallurgical and Foundry Technologies
V. E. Roshchin, Dr. Eng., Prof., Chief Rsearcher, Laboratory of Hydrogen Technologies in Metallurgy, e-mail: roshchinve@susu.ru

The results of experimental studies of the selective reduction of iron from ilmenite concentrate with carbon and hydrogen are presented. It has been shown that hydrogen, as an alternative to carbon as a reducing agent, makes it possible to obtain metallic iron and rutile at a relatively low temperature, which are easily separated upon melting and are commercial products. The higher rate of hydrogen reduction is due to the fact that hydrogen, compared to carbon, is a stronger reducing agent at relatively low temperatures, and also due to its gaseous state of aggregation, which significantly increases the reaction surface in porous briquettes. It has been shown that at a temperature of 900 °C, the reduction of iron from ilmenite with both carbon and hydrogen proceeds with the formation of metallic iron and rutile. At a higher (1000–1100 °C) temperature of the reduction of iron with carbon, the resulting rutile enters into a chemicalinteraction with unreacted ilmenite, resulting in the formation of iron dititanate. The formation of iron dititanate depends on the rate of diffusion processes and does not depend on the type of reducing agent used. At a temperature of 1300 °C, the products of metal reduction from ilmenite with solid carbon are metallic iron and anosovite.
The study was supported by the Russian Science Foundation (grant No. 23-29-10119, https://rscf.ru/project/23-29-10119/)

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