Hydrodynamic modeling of copper electrodeposition at a vertical rotating cylinder electrode

摘要

The hydrodynamics of a rotating cylinder electrode were modeled to predict tertiary current distributions during electrodeposition of copper from acidic sulfate media, and to evaluate the effects of the resulting density gradients close to the electrode. Assuming no such density variations, then predictions of transport-limited current densities were in good agreement with Mizushina's empirical law and with Lévêque's theoretical description, but not with measured values. Assuming a linear density variation with copper concentration, predictions of concentration profiles agreed to within 3 % of experimentally measured limiting current densities at the rotating cylinder electrode. For solution compositions relevant to copper electrowinning, a diffusion coefficient for cupric ions of 1.2×10^-9 m2/s at 45 °C, was inferred by solving the continuity, Navier-Stokes and mass balance equations with Fluent® computational fluid dynamics software.