Management of composition cathodic products in the electrolysis of molybdenum‐, tungsten‐ and carbon‐ bearing halogenide‐oxide and oxide melts

Abstract

It is shown that the cathode products of electrolysis of melts based on a eutectic mixture of sodium chloride and lithium fluoride as well as melts based on sodium tungstate in which dissolved oxides of molybdenum (VI) or tungsten (VI), molybdate, tungstate and lithium or sodium carbonates are molybdenum, tungsten, their bronzes and carbides, carbon.It is established that the phase composition of electrolysis products is determined by the concentration of carbonate in the melt.Particular conditions of plating coating of molybdenum and tungsten carbides on carbon, nickel and copper materials are determined.Molybdenum carbide coatings of electrolyte Na2WO4–Li2MoO4–Li2CO3 are deposited at equality (within 2.5 mol%) of concentrations molybdate and lithium carbonate. However, their concentrations should not exceed 10 mol%. At lower concentrations of molybdate in the precipitate are detected carbon, molybdenum, molybdenum carbide, and at high concentrations – molybdenum oxides. At lower concentrations of carbonate in the sediment dominates molybdenum and at large concentrations mainly free carbon is released. More affordable industrial reagent‐source of molybdenum is its oxide.