Electrode which can be regenerated - consists of oriented carbon or carbide fibres coated with electrochemically active material, and used esp. for electrolytic mfr. of metal

摘要

An electrode with a stable shape is used at high temps., esp. in molten electrolytes, and consists of an assembly of tubes, rods and/or plates, which each have a pref. direction of orientation(PDO) coinciding with the direction of flow of the electric current. The tubes etc. are made of at least one electrochemically active material(I) and electrically conducting inorganic fibres aligned along the PDO. The fibres are pref. embedded in or coated with material(I). The fibres are pref. C; B and/or SiC; TaC; WC; C mixed with sub-stoichiometric TaC, viz. TaC(x) where x is below 1.0; TaC(x) and NbC(x); or C + TaC(x) + NbC(x). The fibres may be mono- or poly- crystalline. Material(I) is pref. a metal-carbide, -boride, -nitride, and/or metal: Ta, TaC, and/or Ta2O5; barium titanates where part of the Ti is replaced by Pt, Ru, or Pd; or a cermet. Used e.g. in the electrolytic mfr. of Al, Mg, Na or Li, where costly carbon electrodes with a short life are normally used. The invention replaces carbon electrodes with assemblies possessing a higher electro-chemical activity; lower internal resistance; and longer life with easy regeneration.