Simulation and validation studies of impurity particle behavior in copper electrorefining

A model based in COMSOL Multiphysics consisting of an electrorefining cell was utilized to simulate copper electrorefining. Concentration and electrolyte density profiles were generated as electrochemical simulation results. Fluid velocity field, particle trajectories, and particle distribution maps were generated to study impurity particle behavior in electrolyte. A three factor designed set of boundary conditions was used to determine the effects of inlet flow rate, temperature, and current density on impurity particle behavior in electrolyte and the associated distribution on the cross section (slice) 100 microns away from the front surface of the cathode during copper electrorefining. The number of impurity particles on the cross section was counted for each set of boundary conditions. The model data for impurity particle distribution was compared with measured impurity particle contamination at the cathode surface, and the results show a very good correlation, which suggests the model is reasonable. The model results show the three factors have significant effects on the number of impurity particles on the cross section. The impurity particle counts at the corner positions of the slice are much higher than those at the center position of the slice. Possible explanations for the simulation results are proposed.