Abstract: An aluminum reduction cell having an outer steel shell, thermal and electrical insulation, and an inner lining comprising at least a floor and sidewalls, the improvement which comprises a gap sealant at least in the region of the transition between the floor and sidewalls, the gap sealant comprises a pourable material characterized by a melting point of greater than 1000.degree. C., a density of greater than 2.7 g/cm.sup.3 and a high degree of resistance to molten electrolyte and molten aluminum.

Abstract: An exchangeable solid cathode such that its average density is less than that of the molten aluminum, as a result of which the said cathode floats projecting into the electrolyte from below. At least three vertical, electrically insulating spacers are attached to the work face of the cathode and, due to the upthrust on the floating cathode, press against the work face of the related anode. The said floating cathode also features stabilizing positioning facilities at the side which insure proper lateral positioning of the cathode.

Abstract: The precipitated liquid metal in a cell for the electrolytic production of aluminum contains, with the exception of its uppermost, freely moveable layer, an electrically conductive granular material.At least one trough containing molten electrolyte saturated with aluminum oxide is provided outwith the vertical projection of the anode or anodes. The top of the trough lies above the surface of the liquid metal, but is always at least partly below the surface of the electrolyte.The direct electric current is conducted away from the molten metal by cathode elements which are wet by aluminum.