MULTI-LAYER NON-CARBON METAL-BASED ANODES FOR ALUMMULTI-LAYER NON-CARBON METAL-BASED ANODES FOR ALUMINIUM PRODUCING CELLS INIUM PRODUCING CELLS

摘要

A composite, high-temperature resistant, non-carbon metal-based anode of a cell for the electrowinning of aluminium comprises a metal-based core structure of low electrical resistance, for connecting the anode to a positi ve current supply, coated with a series of superimposed, adherent, electrically conductive layers. These layers consist of at least one layer on the core structure constituting a barrier substantially impervious to monoatomic oxyg en and molecular oxygen; one or more intermediate, protective layers on the oxygen barrier layer(s) which remain inactive in the reactions for the evolution of oxygen gas; and an electrochemically active layer for the oxidation reaction of oxygen ions present at the anode/electrolyte interface into nascent monoatomic oxygen, as well as for subsequent reaction for the formation of gaseous biatomic oxygen. The active layer comprises at least on e transition metal and/or an oxide thereof (excluding the lanthanides and actinides and their oxides alone).