Electrochemical long-term stability of a choline chloridebased deep eutectic solvent for precious metal recovery

This work investigates the long-term stability of the deep eutectic solvent (DES) Propeline 1:3 (Pr 1:3), composed of choline chloride and propylene glycol, with a particular focus on its stability during silver electroleaching and electrodeposition (EL-ED) processes. The primary objective is to understand the stability and degradation mechanisms of the DES under conditions relevant to industrial applications, rather than focusing on the fundamental electrochemistry of silver in this medium. The study begins with thermal ageing to evaluate the stability of Pr 1:3 during prolonged storage without electrochemical stress, providing a baseline for long-term usability. Forced electrochemical degradation is then studied by applying a constant current over several days in the absence of redox-active