DETERMINATION OF CHLORIDE-ION DIFFUSION-COEFFICIENTS FOR ZINC DISSOLUTION IN A LOW-TEMPERATURE MOLTEN-SALT

The transport properties and stoichiometry of the zinc dissolution process in mixtures of aluminum chloride and 1-methyl-3-ethylimidazolium chloride were studied. A new mass transfer correlation for rotating cylinder electrodes was found for these high Schmidt number electrolytes. Two limiting current regions were observed during the dissolution process which corresponded to a coordination number of four at low overpotentials and a coordination number of three at high overpotentials. The quantity Dμ/T was calculated to be 3.5 × 10-10, which corresponds to a chloride ion radius of 2.1 × 10-8 cm. © 1990.