Studies of the synthesis and stability of inert anodes in electrolysis of alumina-cryolite melts

摘要

Studies on the development of the principles underlying the creation of materials and methods of producing inert anodes of aluminum cells are conducted. Cermet anodes were fabricated by pressing with subsequent sintering or gaseothermic spraying. For -samples that had been obtained by the former method, optimal conditions are found that make it possible to achieve high density and sufficient homogeneity of the composition. For the second method, a technology involving local gas protection was developed and implemented. Synthesis of encapsulated gradient-type composite material in the form of a nonporous multilayer composite material with protective barrier layers has shown promise. The layers are able to increase the resistance simultaneously to the action of atomic oxygen and to electrochemical corrosion in the course of electrolysis. Studies of several types of anodes that differ in terms of production technology and composition of the working layer are conducted. The best of these types of anodes prove to be homogeneous and gradient-type cermet anodes with variable concentration of metallic and oxide phases.