Electrolysis of aluminum in the low melting electrolytes based on potassium cryolite

The aluminum electrolysis in electrolytes with composition (mas.%): KF(47,37)-AlF3(52,63) with CR=1,3 and KF(49,0)-AIF(3)(49,0)-LiF(2,0) with CRKF=1,58 at temperature 750 degrees C was carried out in the lab scale cell with liquid aluminum cathode. As anodes, metallic Al-Cu and Ni-Cu-Al-Fe; cermet Cu-Cu2O; ceramic SnO2 materials were used. The alumina concentration was kept on the 4,5 mas.% level. The region of anode current density was 0,4 divided by 0,6 A/cm(2). Duration of experiments reached 96 hours. Temperature, voltage and current on the cell during electrolysis, voltage at the moment of current interruption were recorded. The most suitable anode materials have proved to be Cu-Al(3 or 5 mas.%) and Cu2O-Cu(15 mas.%) and ceramic based on SnO2.