Composite anode for the electrolytic deposition of aluminum

摘要

An anode is provided for use in the electrolytic deposition of aluminum at low temperatures in which the anode is the sole source of aluminum and comprises a composite mixture of an aluminous material such as aluminum oxide and a reducing agent such as carbon. Conductor means of higher electrical conductivity than the anodic mixture are provided to conduct substantially the entire anodic current to the active anode surface thereby reducing the voltage drop through the highly resistive composite mixture. The conductors may be of aluminum and sized to melt back at substantially the same rate at which the mixture is consumed. The mixture may be employed in a self-baking mode or be pre-baked. Alternatively, the mixture may be in a particulate form and contained within a porous membrane which passes the electrolyte or other dissolved material while withholding undissolved impurities. The membrane may be used with a conductor to provide bipolar electrode faces.