Towards the Stability of Low-Temperature Aluminum Electrolysis

The results of several different tests related to the low-temperature aluminum electrolysis were considered in this work. The role of mass transfer processes in the anode-cathode space was recommended to be significant during electrolysis in the low-temperature KF-AlF3 and NaF-AlF3-based melts. The stationary polarization and voltammetry methods were applied in order to study the kinetics of the electrode processes on the carbon and metal electrodes in the KF-AlF3-Al2O3 melts and to select the electrolysis parameters. The schemes of electrode processes were suggested on the basis of electrochemical tests, the flows of substances in the anode-cathode distance were analyzed and the main reasons of the cathode current efficiency decrease during the low-temperature electrolysis in the KF-AlF3-Al2O3 and KF-NaF-AlF3-Al2O3 melts were discussed. It was revealed that the cathode current density should not exceed 0.4-0.55 A cm(-2) during the electrolysis at 750 degrees C-800 degrees C.

Automated summary

This study considered the results of several different tests related to low-temperature aluminum electrolysis. It is recommended that mass transfer processes in the anode-cathode space play a significant role during electrolysis in low-temperature KF-AlF3 and NaF-AlF3-based melts. It was also found that the cathode current density should not exceed 0.4-0.55 A cm(-2) during electrolysis at 750 degrees C-800 degrees C.