| 摘要 |
A cell for the electrowinning of aluminium comprises a metal-based anode (10 ) containing at least one of nickel, cobalt and iron, for example an anode mad e from an alloy consisting of 50 to 60 weight% in total of nickel and/or cobal t; 25 to 40 weight% iron; 6 to 12 weight% copper; 0.5 to 2 weight% aluminium and/or niobium; and 0.5 to 1.5 weight% in total of further constituents. The anode (10) may have an applied hematite-based coating and optionally a ceriu m oxyfluoride-based outermost coating. The cell contains a fluoride-containing molten electrolyte (5) at a temperature below 940~C, in which the anode is immersed and which consists of: 5 to 14 weight% dissolved alumina; 35 to 45 weight% aluminium fluoride; 30 to 45 weight% sodium fluoride; 5 to 20 weight % potassium fluoride; 0 to 5 weight% calcium fluoride; and 0 to 5 weight% in total of one or more further constituents. A nickel-containing anode stem (14b) can be used to suspend the anode (10) in the electrolyte facing a cathode (21,21A,25) that has an aluminium-wettable surface (20), in particul ar a drained horizontal or inclined surface. |
