Journal of Chemical Engineering of Japan, Vol.39, No.1, 77-82, 2006
Preparation of tantalum powder from Ta2O5 by an electrochemical reduction in an LiCl-Li2O molten salt system
The electrochemical reduction of Ta2O5 in an LiCl-Li2O molten salt system has been studied in an electrolytic cell with an integrated cathode assembly at 650 degrees C. The integrated cathode assembly consists of an electric conductor, Ta2O5 and a porous magnesia membrane. The metallic tantalum is prepared successfully by the mechanism of an electrode reaction followed by a chemical reaction in the range of voltage between -2.47 V and -3.46 V. The chemical and physical properties of the metallic tantalum are influenced by the applied current related to the reaction rate. The XRD analysis indicates that the tantalum samples prepared at the applied current above 1.0 A have both of bee and tetragonal structures. The particle size of those samples is similar to that of the fresh Ta2O5.