Reduction mechanism of oxides in calcium chloride melts

Alternative notions on the reduction mechanism of crystalline metal oxides during the electrolysis of CaCl2 melts, which has been actively discussed worldwide in scientific publications over the last 15 years, are described. It is shown based on the known experimental data on the nature of the Ca-CaCl2 solution and its reduction properties that metal oxides can reduce without direct contact with the cathode in the volume of a homogeneous Ca-CaCl2 salt near cathode, i.e., catholyte. The reducing agent is calcium dissolved in a form of Ca+ cations in this case. The reaction surface area multiply increases in this case, which favorably affects the course of heterophase chemical reactions. The method of introduction of Ca+ ions into the salt melt can be both by electrolysis of CaCl2 or due to the dissolution of metal calcium, and it does not vary the essence of our process model.