Rare earth metals (REM) with magnetic properties find application in the recently developed high-tech industries. Sensor magnetic systems based on neodymium are increasingly in demand in modern engineering and geological surveys due to their favorable combination of properties of magnetic materials based on rare earth metals. One of the problems is to obtain high-quality materials for the production of such magnetic sensors. It should be noted that the high activity of REM does not allow obtaining master alloys and REM-based alloys from metallic materials; it is advisable to use halide compounds. This work discusses a method for producing neodymium fluoride from its oxide. REM fluorides can be obtained by fluorinating the oxides of these metals. Various fluorine-containing compounds or elemental fluorine are usually used as fluorinating reagents, which have their own advantages and disadvantages. The thermodynamic and technological analysis of neodymium fluoride production processes has shown the most acceptable fluorinating agent is ammonium hydrofluoride, which was used in this work. In order to increase the productivity and degree of chemical transformation, it was proposed to perform heating stepwise; i.e., at the initial stage, heat at a speed of 3 degrees per minute, after which the heating speed was reduced to 2 degrees per minute, and finally the speed was reduced to 1 degree per minute. Due to proposed heating mode, the same productivity and yield of chemical transformation were achieved, with an increased efficiency up to 30%, which can significantly reduce the cost of production. The obtained product is used in the production of neodymium-based alloys by metallothermic reduction of a mixture of fluorides. The sensor material obtained in this way is characterized by a low (less than 0.05%) oxygen content.

The oxidability of aluminum powder with carbon dioxide is studied theoretically and experimentally in the scope of the developed technology of the aluminothermic acquisition of metal lithium as a dissociation product of lithium carbonate. Our evaluation of the interaction of solid and liquid aluminum with CO₂, as well as (for comparison) with oxygen, shows that aluminum should be oxidized with two gases both in solid and in liquid states. It is established experimentally that oxide film protects the aluminum of oxidation with carbon dioxide during the dissociation of lithium carbonate. It is proven experimentally that during dissociation the protective layer of Al₂O₃ on the surface of aluminum powder interacts with Li₂CO₃ with the formation of a new denser layer of lithium monoaluminate, which protects the aluminum of oxidation with CO₂ better than Al₂O₃.