Anodic dissolution of aluminum in AlCl3-[BzMIM]Cl ionic liquid

Abstract

• The anodic dissolution behaviors of aluminum in AlCl 3 —1-benzyl-3-methylimidazolium chloride ionic liquid were studied for the first time. • The mechanism of passivation generation was explained in detail, and the passivation products were identified. • The corrosion behaviors of aluminum in AlCl 3 -[BzMIM]Cl ionic liquid were analyzed by electrochemical tests. • To provide the theoretical basis for the extraction of aluminum from AlCl 3 -[BzMIM]Cl ionic liquid. The anodic dissolution behaviors of aluminum in AlCl 3 -[BzMIM]Cl (1-benzyl-3-methylimidazolium chloride) ionic liquid was investigated using coulometric weight loss experiments, linear sweep voltammetry, potentiodynamic polarization and electrochemical impedance spectroscopy. The results showed that passivation occurred during the anodic dissolution of aluminum, and the passivation film was identified as the formation of AlCl 3 precipitates and local solidification of electrolyte on the electrode surface. The potentiodynamic polarization analysis showed that an increase in temperature caused a positive shift in corrosion potential ( E corr ), an increase in corrosion current density ( i corr ) and a decrease in polarisation resistance ( R P ). Impedance measurements indicated that the anodic dissolution process of aluminum in AlCl 3 -[BzMIM]Cl ionic liquids consisted of charge transfer, confinement of the passivated film on the electrode surface and diffusion-induced Warburg impedance.