Theoretical Analysis of Mass Transfer During Anodic Dissolution of Tungsten Rotating Disk Electrode in Alkaline Solutions

The mass transfer during the electrochemical dissolution of metals with the participation of electrolyte anions and the formation of stable anionic complex is analyzed by the example of tungsten anodic dissolution in the alkaline solutions. The distributions of ionic concentrations, partial current densities of ions and potential over the solution layer near the anode are determined as a result of numerical solution of the problem. The results of numerical solution are compared to the results of analytical solution and experimental data available from the literature. It is shown that the numerical solution of the problem with regard for migration, convection and concentration dependences of transport properties of solution agrees well with the experimental data. A complex role of ion migration in this process is revealed.