The volatility of lithium cryolite is determined and electrolysis with the utilization of electrolytes of the new lithium cryolite-based compositions is carried out to evaluate the possibility of their application in industry. Experiments were performed at a temperature of T = 840 deg C. The current efficiency was determined from the metal weight increment. Its maximal value (93.4 percent) was observed in a lithium cryolite-based electrolyte with the additives of potassium (7.4 wt percent) and sodium (16.7 wt percent) cryolites, CaF_2 (4.0 wt percent), and Al_2O_3 (3.0 wt percent). On introduction of K_3AlF_6 (7.4 wt percent) and LiF (2.2 wt percent) into the lithium cryolite-based electrolyte the process of electrolysis is most stable. The evaporation rate from the exposed surface under the conditions of free convection was 1.7487 X 10~(-5) g/(cm~2 s). It is revealed that the proposed electrolyte is vaporized in the form of lithium tetrafluoroaluminate. Therefore from a technological point of view its utilization in industry has good prospects for electrolytic extraction of aluminum.
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