Electrochemical long-term stability of propeline deep eutectic solvent for silver recovery

The use of deep eutectic solvents (DES) is particularly attractive for precious metals electrometallurgy, since is allows the replacement the polluting state-of-the-art hydrometallurgical routes. However, it is conditioned to the DES long term stability under operating conditions, which is to demonstrate. This data set is related to the study of the long term stability of Propeline 1:3 (choline chloride: propylene glycol) deep eutectic solvent both in storage, and under electrochemical operation conditions, using silver electroleaching- electrodeposition process as a model electrochemical system for the DES ageing study. The solvent long term stability is evaluated during prolonged storage without electrochemical stress, providing a baseline for long-term usability. The electrochemical stability window of Propeline 1:3 is then determined, and its electrochemical degradation is forced for several days in order (i) to identify the degradation products formed and (ii) to understand the degradation mechanism that choline chloride - glycol based DES can encounter during extreme operating condition or process malfunction. Finally, Propeline 1:3 long-term stability under operation conditions is evaluated using different electroleaching-electrodeposition current densities by the monitoring of degradation product formation. The impact of DES ageing is on the performances of silver electrometallurgy is assessed using fresh and aged electrolyte. Data provided are : - GC-MS and NMR analysis of degradation products after thermal and/or electrochemical ageing - Photos and SEM images of silver anode and cathode in different electrolysis conditions - electrochemical data such as cyclic voltammetry and chronopotentiometry to assess electrochemical stability and silver electrochemical leaching and electrochemical deposition process.