Evaluation of a pre-oxidation treatment for limiting electrolyte penetration in Cu-Ni-Fe anode during Al electrolysis

Abstract

A comparative study on untreated and pre-oxidized Cu65Ni 20Fe15 inert anodes for aluminium electrolysis in low temperature (700°C) KF-AIF3 electrolyte was conducted. The pre-oxidation treatment was performed at 700°C under Ar-20%O2 for 3 h, leading to the formation of a Cu0-NiFe2O4 layer on the anode. This preformed oxide layer has a positive impact on the anode corrosion resistance by favoring the formation of a denser oxide scale with limited electrolyte infiltration during Al electrolysis. Copyright © 2014 by The Minerals, Metals & Materials Society.