METHOD OF PRODUCING MAGNETITE Russian patent published in 2019 - IPC C22B1/00 C01G49/08 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy and can be used to produce magnetite in order to increase efficiency of processing red mud, which are wastes from alumina production. Method of producing magnetite involves treating red mud in the presence of calcium hydroxide, wherein autoclave treatment of red mud is carried out at temperature of 235–250 °C and pressure of 21–26 MPa while stirring with introduction of 30 % NaOH solution into initial mud at ratio of L:S equal to (4–5):1, and iron (II) salt in amount of 5–25 wt% of initial mud mass. Content of calcium hydroxide is 3–4 wt% of CaO from weight of initial mud.

EFFECT: invention ensures high extraction of the target product, considerable reduction of the process temperature and, as a result, absence of possibility to form iron carbide as an undesirable admixture and necessity in additional crushing and grinding of the target product.

3 cl, 3 ex