Evaluation Of Zinc Sulfate Electrolytes By Cyclic Voltammetry And Electron Microscopy

A cyclic voltammetric technique has been developed for approximating the quantities of active chemical species present in zinc sulfate electrolytes. The experimental apparatus consisted of a Pyrex H cell, an aluminum cathode encased in a Teflon holder, a carbon anode and a mercurous sulfate reference electrode. Voltammograms were obtained using industrial, purified neutral leach solution (Cominco Ltd., Trail, BC) acidified to give a final concentration of 0.77 M Zn++ and 1 M H2SO4. The polarization curves were then evaluated and used as reference standards to compare with results obtained when various organic and inorganic additions were made. The deposit morphologies obtained for short-time cathodic cycles were also studied with the aid of a Scanning Electron Microscope. Changes in concentrations of glue in the 5 to 10 ppm range and of antimony in the 5 to 10 ppb range were detected using the techniques described. © 1976 The Minerals, Metals & Materials Society - ASM International - The Materials Information Society