Patent ID: 6287447
Filing Date: 2001-09-11
Classification: C04B,C25C

Abstract:
A method of producing aluminium in a drained-cathode cell for the electrowinning of aluminium by the electrolysis of alumina dissolved in a molten electrolyte, said cell comprising at least one cathode having a drained cathode surface and a facing anode spaced apart from the cathode in the electrolyte by an anode-cathode gap, the cathode being formed by a body coated with an adherent aluminium-wettable coating of refractory hard metal boride in a dried colloid forming the drained cathode surface, said coating being obtainable by non-reactive sintering or consolidation of preformed particulate refractory hard metal boride in the dried colloid, the method comprising electrolysing the dissolved alumina in the inter-electrode gap to cathodically produce aluminium on the aluminium-wettable drained cathode surface and continuously draining the produced aluminium from the drained cathode surface.