Method for preparing tantalum or niobium powders used for manufacturing capacitors

摘要

Disclosed relates to a method for preparing tantalum or niobium powders used for manufacturing capacitors in an electrolytic reducing reactor including an anode, a cathode and a molten salt, the method comprising: obtaining a tantalum or niobium oxide, expressed by Ta₂O_(5-y) or Nb₂O_(5-y) where y=2.5 to 4.5, from a tantalum pentoxide Ta₂O₅ or a niobium pentoxide Nb₂O₅ generated partially by an alkaline metal electrolytically reduced via a first electrolytic reducing reaction that reduces an alkaline metal oxide from a molten salt comprising at least one metal halogen compound, selected from the group consisting of alkaline metal and alkaline earth metal, and an alkaline metal oxide on the cathode; and preparing a tantalum or niobium powder by a first electrolytic reducing reaction that reduces at least one metal halogen compound selected from the group consisting of the alkaline metal oxide and the alkaline earth metal on the cathode and by a second reducing reaction with the tantalum or niobium oxide, represented by Ta₂O_(5-y) or Nb₂O_(5-y) where y=2.5 to 4.5.